Document:

EX-10.20

 Exhibit 10.20 

[ * ] = Certain confidential information contained in this document, marked by brackets, has been omitted and filed separately with the
Securities and Exchange Commission pursuant to Rule 406 of the Securities Act of 1933, as amended. 
 FIRST AMENDMENT TO 

May 23, 1997 LICENSE AGREEMENT 

The First Amendment to the May 23, 1997 License Agreement (the “1997 License Agreement”) by and between University of Miami
(the “University”) and FibroGen, Inc., and its Affiliates (the “Company”) (collectively, the “Parties”) is effective July 29, 1999. Except as otherwise set forth herein, the defined terms in the 1997 License
Agreement shall be incorporated by reference herein. 
 The Parties hereby agree to amend the 1997 License Agreement as follows: 

1. Section 1.4 shall be amended and restated in its entirety to read as follows: 

“Patent Rights” shall mean the University’s share of (a) United States Patent No. [ * ], United States
Patent Application Serial Number [ * ], and the two United States Patent Applications filed on [ * ] entitled [ * ] for which numbers have not yet been assigned, (b) any applications filed
prior to this date relating to CTGF, homologs to CTGF, [ * ] and/or methods of use or treatment thereof which University’s employees are joint or sole inventors thereon or any applications filed hereafter for which the Company
has provided research funding pursuant to the November 29, 1995 Research Agreement between the Parties, as amended, or any subsequent funding arrangement between the Parties, (c) and the United States and foreign patents issuing from said
United States and foreign patent applications collectively, hereinafter referred to as the “Patent Rights Patent Application”) or later filed domestic or foreign applications based on the said United States Patents and applications
(hereinafter referred to as the “Patent Rights Patents”) and any continuations, continuations-in-part, divisions, reissues or extensions of any of the foregoing. In the event that the University has or acquires any rights to United States
Patent Nos. [ * ]; or United States Patent Application Serial Number [ * ], and foreign application (including PCT No. [ * ]), continuations, continuations-in-part, divisions, reissues or extensions
thereof, such rights shall be included in “Patent Rights”, “Patent Rights Patent Application” or “Patent Rights Patents” as appropriate. 

2. Section 4.1 (b) shall be amended and restated in its entirety to read as follows: 

(b) (i) Subject to clause (ii) below, Company shall pay University a running royalty equal to: 

(x) [ * ] of Net Sales of any Licensed Products and/or the sale of product labeled for a Licensed Method use (a
“Royalty Product”) in cases other than specified in (y) or (z), 
 (y) [ * ] of Net Sales of any Royalty
Product in the case that such Royalty Product is also covered by a patent or patent application owned or held by the University of South Florida. 

 (z) [ * ] of Net Sales of any Royalty Product in the case that any of the
Patent Rights covering such Royalty Product is jointly owned or held by the Company. 
 (ii) The applicable running royalty set forth in
Section 4.2.(b)(i) may be reduced by any royalty obligations of the Company to other third parties (except the University of South Florida) on the sale of Royalty Products; provided, however that the University’s royalties shall not be
offset by more than seventy-five percent (75%) (i.e. so that the royalty rate may be reduced to [ * ] in (b)(i)(x) or [ * ] in (b)(i)((y) and (z)). In the event that the Company reduces the royalty to the
University pursuant to the foregoing, the Company must disclose to the University the third party royalty payment and the identity of such third party. 

3. Section 4.1(c) shall be amended and restated in its entirety to read as follows: 

The Company shall pay the University milestone payments on the first Royalty Product to reach the following milestone in the first major country (United
States, Japan, U.K., France, Italy, Spain or Germany): 
  

					
	 Upon acceptance of an IND with the FDA or commencement of any human clinical trial
	  	$	[ * ]	  
		
	 Upon successful completion of Phase II in the U.S. (or comparable foreign clinical trial)
	  	$	[ * ]	  
		
	 Upon written notice of FDA (or comparable foreign body) approval for marketing
	  	$	[ * ]	  

 In no event shall the foregoing be construed to require the Company to pay any of the above milestones the
University more than once. 
 In addition, the Company shall pay the University $[ * ] for any subsequent approval by the
first of the FDA or comparable foreign body in a major country for an additional indication for such previously approved Royalty Product or additional Royalty Product (but not the same indication or same Royalty Product in additional markets or
countries). 
 Payment to the University by the Company shall be made within [ * ] days of the achievement of the
applicable milestone. 
 4. Section 4.4 shall be deleted. 

5. With respect to the United States Patent Application No. [ * ] filed in [ * ] and any divisionals,
continuations or continuations in part thereof or foreign counterparts filed relating to the foregoing, the Company shall pay no more than a [ * ] royalty in total to the University and/or University of South Florida on sales of
Royalty 

  
 [ * ] = Certain
confidential information contained in this document, marked by brackets, has been omitted and filed separately with the Securities and Exchange Commission pursuant to Rule 406 of the Securities Act of 1933, as amended. 

 
Products and to the extent that questions of inventorship arise as to whether the patent covers such Royalty Product or whether the University should be included as an assignee to such patent,
such issue shall be resolved by mutually agreed upon third party patent attorney. The royalty shall be allocated based upon the proportion of patents held by each institution or such other reasonable method of allocation agreed to by the Parties in
good faith. For example, assuming that no other offsets apply, if University has 1 solely-held patent, University of South Florida has 3 solely-held patents and they jointly-hold 1 patent, then University of South Florida would be entitled to 70%
(3.5/5) and the University would be entitled to 30% (1.5/5) of the [ * ] royalty. Accordingly, the University of South Florida would receive a [ * ] royalty and the University would receive a
[ * ] royalty. This Section 5 would not be effective unless University of South Florida agrees to a comparable provision. 

6. Section 6.1 is amended to add the following sentence: 

The University agrees that the Company shall control the prosecution and maintenance of the United States Patent Applications filed on
[ * ] entitled [ * ] and any other Patent Rights Patents. 
 Except as set forth above, the 1997 License
Agreement shall remain in full force and effect in accordance with all other terms and conditions specified therein. 
 IN WITNESS WHEREOF,
the parties have executed this Amendment as of the date set forth below. 
  

							
	UNIVERSITY OF MIAMI
				
	 /s/ Alan Fish
	 		 	Date:	 	 8/5/99

				
	FIBROGEN, INC.	 		 		 	
				
	 /s/ Thomas B. Neff
	 		 	Date:	 	 8/3/99

	Thomas B. Neff	 		 		 	
	Chief Executive Officer	 		 		 	

  
 [ * ] = Certain
confidential information contained in this document, marked by brackets, has been omitted and filed separately with the Securities and Exchange Commission pursuant to Rule 406 of the Securities Act of 1933, as amended.EX-10.21

 Exhibit 10.21 

CONFIDENTIAL 
 RESEARCH
AND COMMERCIALIZATION AGREEMENT 
 THIS RESEARCH AND COMMERCIALIZATION AGREEMENT (the “Agreement”), effective as of
July 9, 1998, is entered by and between GenPharm International, Inc., a wholly owned subsidiary of Medarex, Inc., and Medarex, Inc., a New Jersey corporation, with a principal place of business at 1545 Route 22 East, Annandale, New Jersey 08801
(together “Medarex”), and FibroGen, Inc. and its wholly-owned subsidiary, FibroPharma, Inc., with a principal place of business at 225 Gateway Boulevard, South San Francisco, California 94080 (together “FibroGen”). 

BACKGROUND 
 A. Medarex is
the sole and exclusive owner of certain transgenic Mice useful for the preparation of fully human monoclonal antibodies; 
 B. FibroGen
desires to have Medarex conduct research with the Mice for the development of fully human monoclonal antibodies to certain Antigens (as defined below) and to evaluate the utility of such antibodies as potential therapeutics involved in fibrosis or
fibroproliferative disease, and Medarex is willing to conduct such Research, on the terms and conditions herein; and 
 C. FibroGen wishes
to acquire from Medarex an option to acquire a commercial license for the use of monoclonal antibodies with specificity for the Antigens to commercialize Products (as defined below), on the terms and conditions herein. 

NOW, THEREFORE, Medarex and FibroGen agree as follows: 
  

	1.	DEFINITIONS 

 1.1 “Affiliate” means any corporation or other entity
which is directly or indirectly controlling, controlled by or under the common control with FibroGen. For the purpose of this Agreement, “control” shall mean the direct or indirect ownership of fifty percent (50%) or more of the
outstanding shares or other voting rights of the subject entity to elect directors, or if not meeting the preceding, any entity owned or controlled by or owning or controlling at the maximum control or ownership right permitted in the country where
such entity exists. 
 1.2 “Antibody” shall mean a human monoclonal antibody with binding affinity for an Antigen, which
antibody is derived from cells obtained from one or more of the Mice. 

  
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 1.3 “Antigen” shall mean each of twelve (12) antigens listed on Exhibit
A hereto as such list may be revised from time to time by the mutual agreement of the parties. 
 1.4 “Confidential
Information” shall mean (i) any proprietary or confidential information or material in tangible form disclosed hereunder that is marked as “Confidential” at the time it is delivered to the receiving party, or
(ii) proprietary or confidential information disclosed orally hereunder which is identified as confidential or proprietary when disclosed and such disclosure of confidential information is confirmed in writing within thirty (30) days by
the disclosing party. 
 1.5 “Control” or “Controlled” shall mean possession of the ability to grant the
licenses or sublicenses as provided for herein without violating the terms of any agreement or other arrangement with any third party. 

1.6 “Effective Date” means forty-five (45) days after the date of this Agreement. 

1.7 “Excluded Claim” shall having the meaning set forth in the Cross License Agreement entered into by GenPharm
International, Inc. and Cell Genesys, Inc., Abgenix, Inc., Xenotech, L.P., and Japan Tobacco, effective March 26, 1997. 
 1.8
“FibroGen Technology” shall mean all United States and foreign patents (including all reissues, extensions, substitutions, confirmations, re-registrations, re-examinations, revalidations and patents of addition) and patent
applications (including, without limitation, all continuations, continuations-in-part and divisions thereof) owned by FibroGen during the term of the Agreement, in each case, which claims an invention which is necessary or useful to make, use or
sell Antibodies and/or Products. 
 1.9 “Medarex Fees” shall mean any commercial fee, milestone payment and one-half of any
research support payment made by FibroGen to Medarex pursuant to Sections 2.2, 4.1 and 4.2. 
 1.10 “Medarex Technology”
shall mean the Patent Rights and Know How. 
 1.10.1 “Know How” shall mean the Confidential Information and Mice owned or
Controlled by Medarex during the term of the Agreement and transferred to FibroGen by Medarex necessary or useful for the exercise of the Patent Rights, including, without limitation, technical data, protocols and methods and processes. For the
avoidance of doubt, the Know How does not include any Patent Rights. 
 1.10.2 “Patent Rights” shall mean all United States
and foreign patents (including all reissues, extensions, substitutions, confirmations, re-registrations, re-examinations, revalidations and patents of addition) and patent applications (including, without limitation, all continuations,
continuations-in-part and divisions thereof) owned or Controlled by Medarex during the term of the 

  
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Agreement, in each case, which claims an invention which is necessary or useful for the use of the Antibodies or the hybridoma cell lines transferred hereunder to make, use or sell Products. 

1.11 “Mice” shall mean immunizable transgenic mice containing unrearranged human immunoglobulin genes. 

1.12 “Mice Materials” shall mean any parts or derivatives of the Mice prepared by Medarex in connection with the Research,
including without limitation, cells, hybridomas Antibodies, genes, DNA sequences or other biological materials derived directly or indirectly from the Mice. 

1.13 “Net Sales” shall mean, with respect to Section 4.3.1(a), the amount received by FibroGen or its Affiliates, and
with respect to clause (i) of Section 4.3.1(b) and Section 4.3.1(c), the amount received by Sublicensees, for the sale of Products to bona fide independent third parties, less to the extent included in such amount (i) normal and
customary rebates, and cash and trade discounts, actually taken, (ii) sales, use and/or other excise taxes or duties, actually paid, (iii) the cost of any bulk packages and packing, and (iv) amounts actually allowed or credited due to
returns paid and separately identified on the invoice or other documentation maintained in the ordinary course of business. All sales of Products between FibroGen and its Affiliates and Sublicensees shall be disregarded for purposes of computing Net
Sales, unless such a purchaser is the end-user of such Product, A “sale” shall include any transfer or other disposition for consideration, cash or otherwise; provided, it is understood that Net Sales shall not include amounts received by
FibroGen for the purchase of equity, research and development funding, license fees, milestone payments, or reimbursements paid by Sublicensees to FibroGen for milestone payments or research payments paid by FibroGen to Medarex. In no event shall
Sublicensee Revenues be included in Net Sales. 
 In the case of discounts on “bundles” of products or services which include Products, FibroGen
may calculate Net Sales by discounting the bona fide list price of such product by the average percentage discount of all products of the selling party and/or its Affiliates or Sublicensees in a particular “bundle”, calculated as follows:

 Average percentage 

discount on
a                    =        (1 - A/B) x 100 

particular bundle: 
 where A equals
the total discounted price of a particular “bundle” of products, and B equals the sum of the undiscounted bona fide list prices of each unit of every product in such “bundle”. FibroGen shall provide Medarex documentation,
reasonably acceptable to the other party, establishing such average discount with respect to each “bundle”. If FibroGen cannot so establish the average discount of a “bundle”, Net Sales shall be based on the undiscounted list
price of the products in the “bundle”. If a Product in a “bundle” is not sold separately and no bona fide list price exists for such Product, 

  
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the parties shall negotiate in good faith an imputed list price for such Product, and Net Sales with respect thereto shall be based on such imputed list price. 

1.14 “Phase I”, “Phase II” and “Phase III” shall mean Phase I (or Phase I/II), Phase II,
and Phase III clinical trials, respectively, in each case as prescribed by the U.S. Food and Drug Administration or a corresponding foreign entity. 

1.15 “Product” shall mean any product for the treatment or diagnosis of human disease containing an Antibody provided by
Medarex or produced from any hybridoma provided by Medarex or a portion thereof. 
 1.16 “Research” shall mean the
activities conducted by FibroGen and Medarex in the Research Period in connection with the development and assessment of the usefulness and effectiveness of the Antibodies. 

1.17 “Research Invention” shall mean any invention by Medarex or FibroGen in connection with the performance of the Research.

 1.18 “Research Period” shall mean the period from the Effective Date until the earlier of (i) the first anniversary
of the Effective Date, unless the Research Period is extended pursuant to Section 2.6, in which case the last day of the extension period, or (ii) the termination of the Research or the Agreement. 

1.19 “Sublicensee” shall mean a third party (except an Affiliate) to whom FibroGen has granted a license or sublicense to
make, have made, import, use, sell, offer for sale or otherwise exploit Products in the Territory. As used in this Agreement, “Sublicensee” shall also include a third party (except an Affiliate) to whom FibroGen has granted the right to
distribute a Product. 
 1.20 “Sublicensee Revenues” shall mean all amounts (except royalties) received by FibroGen from a
Sublicensee with respect to a grant of rights to the Medarex Technology and/or FibroGen Technology or the right to sell Products, including without limitation, option fees, license fees and milestone payments. Notwithstanding the foregoing, the
parties agree that “Sublicensee Revenues” shall exclude any purchases of equity in FibroGen at fair market value, reimbursements paid by Sublicensees to FibroGen for any payments hereunder and (a) prior to the commencement of Phase
III clinical trials for any Product, on a Product-by-Product basis, any research and development funding, whether paid in advance or as reimbursement for work performed (except research and development funding in excess of FibroGen’s fully
allocated costs of conducting the funded research and development, as determined in accordance with U.S. GAAP) and (b) upon the commencement of Phase III clinical trials for any Product, on a Product-by-Product basis, and thereafter, any
project funding for such Product, whether paid in advance or as reimbursement for work performed (except funding in excess of FibroGen’s reasonably allocatable direct and indirect project expenses). 

  
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 FibroGen agrees that it will not disguise any license fees or milestone payments in the form of research and
development funding. In no event shall Sublicensee Revenues include any amounts received from Sublicensee with respect to Net Sales of any Product. 

1.21 “Territory” shall mean all countries of the world. 

 

	2.	RESEARCH 

 2.1 Research. Subject to the terms and conditions set forth herein,
during the Research Period Medarex will immunize Mice with up to twelve (12) Antigens selected by FibroGen to produce Antibodies for evaluation by FibroGen for commercial development. FibroGen shall have the right to have immunizations for up
to two (2) Antigens conducted concurrently. FibroGen shall be entitled to have Medarex immunize a total of fifty (50) Mice each year; provided, however, that with respect to three Antigens to be selected by FibroGen (“Special
Antigens”), Medarex shall immunize twenty (20) Mice for each of the Special Antigens. In any year in which immunizations for a Special Antigen are conducted, the number of Mice which Medarex is obligated to immunize Mice against Antigens
other than Special Antigens shall be reduced by thirteen and one-third (13 1⁄3) Mice for each Special Antigen for which immunizations are conducted in
such year. For the remaining Antigens with respect to which immunizations are conducted, Medarex shall immunize a minimum of ten (10) Mice with the applicable Antigen. In each case, Medarex shall isolate Antibodies from the immunized Mice as
soon as practicable. FibroGen shall have the option to direct Medarex to immunize the Mice and, on a rolling basis, fuse all the resulting spleens, unless otherwise agreed by a committee consisting of one (1) scientist selected by Medarex and
one (1) scientist selected by FibroGen. FibroGen acknowledges that the exercise of the rolling basis option may delay the receipt of all Antibodies. Medarex shall use reasonably diligent efforts to conduct the Research in a professional manner
and agrees to commit the personnel, facilities and other resources necessary to perform its obligations under the Research and the work plan attached hereto as Exhibit B; provided, however, it does not warrant that the Research shall result in the
preparation of any Antibody suitable for development as a Product or that immunizations with five (5) Antigens can be completed in the initial year of the Research Period. Notwithstanding the foregoing, Medarex shall warrant that FibroGen shall
have the ability to conduct immunization with at least three (3) Antigens in any year of the Research Period. Medarex shall perform tasks 1-6 of the work plan except that FibroGen shall be responsible for testing for neutralization as part of
task 6. During the Research Period, all Antigens shall be considered exclusive to FibroGen in accordance with Section 2.6.5. 
 2.2
Research Support. During the Research, FibroGen shall pay to Medarex a quarterly research support payment of ninety-five thousand dollars ($95,000). The first payment shall be due forty-five (45) days from the Effective Date, and
subsequent payments shall be due on the quarterly anniversary thereof unless work is suspended pursuant to Section 2.6.1; provided that Medarex is not 

  
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in breach of this Agreement. However, if FibroGen fails to make any research support payment for any reason, Medarex shall have no obligation to conduct any further Research activities. 

2.3 Identification and Delivery of Antigens. FibroGen shall promptly notify Medarex of each Antigen prior to immunization of the Mice
in the Research and deliver to Medarex a mutually agreed quantity of such Antigen in a substantially pure form prior to the immunization. 

2.4 Delivery of Antibodies. Upon the preparation of an Antibody for each Antigen, Medarex shall deliver to FibroGen ten
(10) milligrams of such Antibody and a hybridoma cell line producing such Antibody for evaluation by FibroGen. 
 2.5 Research
License. Medarex hereby grants to FibroGen and its Affiliates an exclusive, non-transferable license solely to use the Antibodies and hybridoma cell lines producing such Antibodies prepared by Medarex in connection with the Research for research
and evaluation purposes; provided, however, that FibroGen and its Affiliates may transfer the Antibodies and hybridoma cell lines producing such Antibodies to its scientific collaborators and consultants for purposes of furthering the Research. Such
license shall convert into a non-exclusive research only license upon the termination of the Research, if FibroGen does not acquire a commercial license pursuant to Section 3.1.2; provided, upon the termination of the Research, FibroGen shall
promptly return to Medarex, or destroy, all hybridoma cell lines provided by Medarex (and progeny thereof) which produce Antibodies to which FibroGen has not acquired a commercial license from Medarex. 

2.6 Research Period. 

2.6.1 Suspension. With notice to Medarex at least thirty (30) days prior to the proposed date of suspension, FibroGen may suspend
Medarex’s work under this Agreement, its obligations to, make the Research support payment under Section 2.2 relating thereto and the lapse of the commercial option pursuant to Section 3.1 at any time during the Research Period with
respect to each Antigen, for a period of up to forty-five (45) days after FibroGen (i) receives an Antibody for the applicable Antigen, which Antibody is acceptable to FibroGen, or (ii) after Medarex has conducted Research for at
least six (6) months with regard to the applicable Antigen, FibroGen determines that a suitable Antibody to the applicable Antigen cannot be made, in each case, to allow FibroGen to prepare the next Antigen for immunization hereunder. In
addition, if FibroGen does not have adequate preclinical data to evaluate an Antibody candidate at the end of the Research Period, FibroGen may with notice to Medarex extend the Research Period for up to nine (9) additional months without any
Research support payments solely to obtain in-vivo proof of concept and to evaluate whether to exercise the commercial option with respect to such Antibody. FibroGen shall also give Medarex at least fifteen (15) days notice prior
to having Medarex resume its work hereunder. During the applicable suspension period, FibroGen’s obligations to make Research support payments to Medarex and Medarex’s obligations to conduct any Research shall be suspended. 

  
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 2.6.2 Extension. With notice to Medarex at least thirty (30) days prior to the
first anniversary of the Effective Date, FibroGen may extend the term of the Research until the second anniversary of the Effective Date and, with notice to Medarex at least thirty (30) days prior to the second anniversary of the Effective
Date, FibroGen may further extend the term of the Research until the third anniversary of the Effective Date, and in each case, FibroGen shall continue to make quarterly research support payments as provided in Section 2.2. If FibroGen
(i) extends the Research Period for at least six (6) months (so that the Research Period is at least eighteen (18) months and Medarex has received at least five hundred seventy thousand dollars ($570,000) of research support payments
pursuant to Section 2.2), and (ii) exercises its option and acquires a commercial license pursuant to Section 3.1.2, then FibroGen shall be considered to have exclusivity of all the Antigens listed on Exhibit A in accordance with
Section 2.6.5. 
 2.6.3 If No Extension: Option Antigens. If FibroGen fails to provide Medarex with notice at least thirty
(30) days prior to the first anniversary of the Effective Date that it will not extend the Research for at least six (6) months (i.e., until at least eighteen (18) months following the Effective Date so that Medarex will receive at
least five hundred seventy thousand dollars ($570,000) of research support payments pursuant to Section 2.2), then before the first anniversary of the Effective Date, if FibroGen has exercised its option and acquires a commercial license
pursuant to Section 3.1.2, FibroGen may select six (6) of the Antigens for which FibroGen shall have exclusivity in accordance with Section 2.6.5, and with respect to the remainder (each an “Option Antigen”) FibroGen shall
have an option to obtain exclusivity and shall concurrently with its selection above notify Medarex of the identity of such Option Antigens. With respect to each Option Antigen, during the Research Period FibroGen shall have an option to immunize
against such Option Antigens and/or preclude Medarex from immunizing Mice against such Option Antigens. FibroGen may exercise its option by providing notice to Medarex identifying the Option Antigen and concurrently paying to Medarex fifty thousand
dollars ($50,000) for such Option Antigen. In addition, before entering into a written agreement with a third party to immunize Mice with any Option Antigen, Medarex shall notify FibroGen, and FibroGen shall have ten (10) business days to
exercise its option for the applicable Option Antigen by notifying Medarex that it wishes to retain its rights to such Option Antigen and concurrently paying to Medarex fifty thousand dollars ($50,000) for such Option Antigen. 

2.6.4 Option Antigen Immunization Terms. In the event that FibroGen exercises its option pursuant to Section 2.6.3 with respect to
any Option Antigen and wishes to have Medarex immunize Mice against such Option Antigen, the parties shall agree on amendments to this Agreement which shall specify the schedule of such immunizations and a Research Period for such Option Antigen.
FibroGen shall have the right to acquire a commercial license to any Antibodies against such Antigen as provided in Section 3.1.2, subject to the terms and conditions of this Agreement, including, without limitation, the payments required under
Article 4. 

  
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 2.6.5 Exclusivity. 

(a) During the Research Period, Medarex shall be precluded from (i) knowingly immunizing or permitting any third party to immunize any
Mice against any Antigen, (ii) granting any third party a commercial license under the Medarex Technology which covers such Antigen or any Antibodies specifically directed to the Antigen, or (iii) using any Antibodies derived from the
Research except to the extent necessary to (y) perform the services and research for-the benefit of FibroGen pursuant to this Agreement, or (z) prosecute patent applications pursuant to Section 2.7.2 and Article 10 herein. 

(b) For any Antigen that FibroGen is deemed to have exclusivity, after the Research Period, Medarex shall be precluded from
(i) knowingly immunizing or permitting any third party to immunize any Mice against any such Antigen, (ii) granting any third party a commercial license under the Medarex Technology which covers the Antigen or any Antibodies specifically
directed to the Antigen or (iii) using any Antibodies derived from the Research except to the extent necessary to (y) perform the services and research for the benefit of FibroGen pursuant to this Agreement, or (z) prosecute patent
applications pursuant to Section 2.7.2 and Article 10 herein. 
 (c) Notwithstanding Sections 2.6.5(a) and (b) above, it is
understood and agreed that Medarex is in the business of providing Mice to third parties for research and evaluation, and grants research licenses for such activities, and that one or more of third parties may, without the knowledge of Medarex,
immunize Mice against one or more of the Antigens. 
 2.7 Ownership. 

2.7.1 Mice. Except as provided in Section 3.3, title to the Mice and Mice Materials shall at all times remain with Medarex. 

2.7.2 Intellectual Property. 

(a) Any Research Invention that is or relates to the Mice or Mice Materials shall be owned solely by Medarex, subject to subsections 2.7.2(b)
and (c) below. Any Research Invention made by FibroGen in the course of activities in connection with the Research that is or relates to the Antigens shall be owned solely by FibroGen. 

(b) Medarex shall own all claims in patent applications and patents claiming Research Inventions directed to (i) one or more
compositions of matter (e.g., an Antibody), except formulations of Antibodies for therapeutic or diagnostic use, or (ii) one or more methods of production. 

  
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 (c) FibroGen shall own all claims in patent applications and patents claiming Research
Inventions directed to (i) one or more methods of use of an Antibody, or (ii) formulations of Antibodies for therapeutic or diagnostic use. 

(d) It is understood and agreed that any patent applications and patents containing claims owned by Medarex pursuant to Section 2.7.2(b)
shall be included in the Medarex Technology and shall be subject to (i) any commercial licenses to Antibodies granted to FibroGen pursuant to Section 3.1.2 herein to the extent that such claims cover an Antibody to which FibroGen acquires
a commercial license, or (ii) any nonexclusive license granted to FibroGen pursuant to Section 3.2. 
 (e) FibroGen hereby agrees
to grant and grants to Medarex an exclusive (subject to any nonexclusive license granted to FibroGen pursuant to Section 3.2), worldwide, royalty-free, perpetual, irrevocable license, with the right to grant and authorize sublicenses, to all
claims subject to Section 2.7.2(c) for all uses, excluding any use of any Antibody, or any formulation of any Antibody, in each case, to which FibroGen has acquired a commercial license. 

(f) The parties agree to cooperate and consult with each other with respect to any claims covering Research Inventions subject to
Section 2.7.2 which FibroGen or Medarex wishes to file in any patent office. The parties further agree that if a party wishes to file patent applications relating to a particular Antibody to which the other party has an ownership interest
pursuant to this Section 2.7.2, then the other party shall be given at least thirty (30) days notice and, if it also wishes to file at that time a patent application relating to such Antibody, the two parties’ applications shall be
filed simultaneously, by way of submission in the same envelope or some such similar means. 
 2.7.3 Assignment. At the request of
either party, the parties shall discuss in good faith the assignment by one party to the other of any patent application claiming any Research Invention. In the event that the parties agree that it is advantageous for one party to solely own any
patent application claiming any Research Invention in order that the scope of the patent coverage may be broadened (i.e., terminal disclaimer), the ownership of such patent application shall be assigned to such party by the other party (the
“Assigning Party”). However, in the case of such assignment (a) if the Assigning Party is Medarex, the sole owner shall be deemed to grant to the Assigning Party an exclusive (subject to any nonexclusive license granted to FibroGen
pursuant to Section 3.2), worldwide, royalty-free, perpetual, irrevocable, license under the applicable patent applications or patents, with the right to sublicense, for all uses, excluding any use of any Antibody, or any formulations of any
Antibody, in each case, to which FibroGen has acquired a commercial license, and (b) if the Assigning Party is FibroGen, the applicable patent applications or patents shall be included in the Medarex Technology and shall be subject to
(i) any commercial licenses to Antibodies granted to FibroGen pursuant to Section 3.1.2 herein to the extent that the claims thereof 

  
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cover an Antibody to which FibroGen acquires a commercial license, or (ii) any nonexclusive license granted to FibroGen pursuant to Section 3.2. 

 

	3.	OPTION; COMMERCIAL LICENSE 

 3.1 Option; License. 

3.1.1 Option. During the Research Period, FibroGen shall have an option to obtain an exclusive (even as to Medarex), worldwide
commercial license as set forth in Section 3.1.2 solely to develop Antibodies for use in the development and commercialization of Products. FibroGen may exercise such option by notice to Medarex during the Research Period specifying one or more
Antibodies (up to three (3) per Antigen) to be covered by the commercial license and concurrently paying to Medarex the applicable license fee due pursuant to Section 4.1. If FibroGen has not previously exercised its option to acquire a
commercial license and achieves any milestone subject to Section 4.2, then FibroGen shall be deemed to have exercised its option to acquire a commercial license and shall pay to Medarex the commercial license fee due pursuant to
Section 4.1 within thirty (30) days of the achievement of such milestone, in addition to the applicable milestone fee due pursuant to Section 4.2. 

3.1.2 Commercial License. Effective upon FibroGen’s election to acquire a commercial license, subject to the terms and conditions
of this Agreement, including without limitation, the payment of the license fee set forth in Section 4.1, Medarex grants to FibroGen and its Affiliates the following licenses: 

(a) an exclusive, worldwide, non-transferable (except as set forth in Section 14.3), royalty bearing license under the Medarex
Technology with the right to sublicense, to use hybridomas delivered by Medarex to FibroGen to make or have made Antibodies, and 
 (b) an
exclusive, worldwide, non-transferable (except as set forth in Section 14.3), royalty bearing license under the Medarex Technology with the right to sublicense, to use Antibodies made in the Research to make, have made, import, have imported,
use, offer for sale and sell Products. 
 During the term of the commercial licenses above, Medarex shall not grant any third party a license under the
Medarex Technology which covers Antigens to which Antibodies have been made in the Research or Mice Materials developed in connection with the Research. 

3.2 Non-Exclusive License. If (i) as a result of the conduct of the Research, Medarex has filed a patent application or patent
covering an antibody directed to an Antigen or a method of use of an Antibody for treatment of a specific human disease, and (ii) FibroGen elects not to commercially develop an Antibody provided by Medarex to FibroGen hereunder but wishes to
commercialize 

  
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 another human or humanized monoclonal antibody with specificity for the same Antigen, and would require a
license under the patent applications and patents subject to (i) above to develop or commercialize any product containing such a human monoclonal antibody, then, regardless of whether FibroGen acquires a commercial license from Medarex pursuant
to Section 3.1.2 with respect to a particular Antibody provided by Medarex to FibroGen hereunder, at FibroGen’s request after the Research Period, Medarex shall be deemed to grant to FibroGen, a non-exclusive, worldwide, perpetual,
nontransferable (except as set forth in Section 14.3), royalty-free license under any patent applications or patents within Medarex Technology described in subSections 2.7.2(b) and (c) above, with the right to sublicense, to make, have
made, import, have imported, use, offer for sale and sell products which are independently developed by or on behalf of FibroGen without any use of (x) any Medarex Technology, or (y) any information relating to or derived from any
Antibody, including, without limitation, any DNA or protein sequence information regarding any Antibody or any gene encoding all or part of an Antibody; provided, however, that in no event should clauses (x) or (y) be construed to preclude
the use of any information by FibroGen or its collaborators which (i) was known prior to receipt of the information derived from any Antibody or from Medarex, as shown by contemporaneous written evidence, (ii) was developed or obtained
from sources independent of the information derived from any Antibody or from Medarex, as shown by contemporaneous written evidence, or (iii) was public knowledge or becomes public knowledge in the future, other than through the acts or
omissions of FibroGen or its collaborator(s) or the publication of any patent application with respect to which Medarex is an assignee or a licensee. It is understood and agreed that under this Section FibroGen shall not be granted any license or
other rights to any Antibody except as expressly set forth in Section 2.5, and that FibroGen may not commercialize any such Antibody or any antibody based on or derived therefrom, in whole or part, without obtaining a commercial license from
Medarex pursuant to Section 3.1.2. 
 3.3 Title. If FibroGen acquires a commercial license pursuant to Section 3.1.2, title
to all Antibodies and cells capable of producing Antibodies obtained by FibroGen during the Research Period and the term of such license shall be vested in FibroGen. 

3.4 Regulatory Assistance. If FibroGen acquires a commercial license to a particular Antibody, at the written request of FibroGen,
Medarex shall provide any documentation necessary or appropriate for regulatory filings relating to the origin or modification of the Antibodies or the hybridoma. 

3.5 Retained Rights; No Further Rights. Only the license granted pursuant to the express terms of this Agreement shall be of any legal
force or effect. No other license rights shall be granted or created by implication, estoppel or otherwise. It is understood and agreed that Medarex shall retain rights to make, have made, import, use, offer for sale, sell and otherwise
commercialize Mice which have not been used for the Research or immunized with any Antigen, itself or with third parties for any uses. 

  
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	4.	CONSIDERATION 

 4.1 Commercial License Fee. If FibroGen acquires a commercial
license from Medarex pursuant to Section 3.1.2 above, FibroGen shall pay to Medarex a license fee of one million dollars ($1,000,000). The applicable license fee shall be paid to Medarex concurrently with FibroGen’s notice of its exercise
of its option. 
 4.2 Milestone Payments. Within thirty (30) days following the occurrence of the relevant events specified
below with respect to each Product which contains one of the Antibodies licensed by FibroGen (under a research license or a commercial license) and is intended to be used as a therapeutic, FibroGen shall pay to Medarex the following amounts: 

 

					
	 Milestones
	  	Amount	 
	 Commencement of Phase II clinical trials
	  	$	1,000,000	  
	 Commencement of Phase III clinical trials
	  	$	2,000,000	  
	 First BLA filing in the U.S., Japan or Europe
	  	$	2,000,000	  
	 First BLA approval in the U.S., Japan or Europe
	  	$	4,000,000	  
	 BLA approval in a second major market in the U.S., Japan or Europe
	  	$	2,000,000	  

 4.3 Royalties and Sublicensee Revenues. 

4.3.1 Royalty on Net Sales and Sublicense Revenues. 

(a) In partial consideration for the commercial license, FibroGen shall pay to Medarex a royalty of (i) one and one-half percent
(1.5%) on annual Net Sales of FibroGen and its Affiliates of Products sold as therapeutics, on a Product-by-Product basis, and (ii) ten percent (10%) on annual Net Sales of FibroGen and its Affiliates of Products sold as in vivo or ex
vivo diagnostics, on a Product-by-Product basis. In addition, for each diagnostic Product, on a Product-by-Product basis, in the event that Net Sales of FibroGen and its Affiliates exceeds fifty million dollars ($50,000,000) in any year, Medarex
shall receive an additional royalty of two and one-half percent (2.5%) on the annual Net Sales in excess of the $50 million (the “Bonus Royalties”) until such time as Medarex has received a total of ten million dollars ($10,000,000)
of Bonus Royalties with respect to such Product. 
 (b) In addition to the above, in partial consideration for the commercial license,
FibroGen shall pay to Medarex, at FibroGen’s option, either (i) a royalty of one and one-half percent (1.5%) on annual Net Sales by Sublicensees of FibroGen and its Affiliates of Products sold as therapeutics, on a Product-by-Product
basis (and no portion of Sublicensee Revenues); or (ii) seventeen and one-half percent (17.5%) of (x) all payments of royalties received by FibroGen and/or its Affiliates in respect of the sale by a Sublicensee of any Product sold as
a therapeutic and (y) all Sublicensee Revenues relating to therapeutic Products or rights thereto received from such 

  
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 Sublicensee; provided, however, that in reference to clause (y): (1) with respect to Sublicensee Revenue
received by FibroGen prior to the date any Medarex Fees are paid by FibroGen to Medarex, FibroGen may fully credit any amounts paid pursuant to clause (y) against the Medarex Fees (and not previously applied against) until such credit is fully
expended; (2) with respect to Sublicensee Revenues payments received by FibroGen from a Sublicensee after the date any payment of a percentage (i.e., 17
 1⁄2%) of the Sublicensee Revenues (the “Medarex Share”) or Medarex Fee is made by FibroGen to Medarex, FibroGen may subtract from Sublicensee
Revenue payments the amount of any Medarex Share or Medarex Fees previously paid to Medarex (and not previously subtracted), and make the required payments (i.e., 17  1⁄2%) to Medarex on the remainder; and (3) upon the termination of the Product development or the termination of the Sublicensee Revenues for any reason, the amounts received by Medarex under clause
(y) and the Medarex Fees shall be subject to a reconciliation which shall compare the amounts received by Medarex against the amount to which Medarex is entitled (Z), which shall be calculated as follows: 

Amount Medarex is entitled = Z + amount of Medarex Fees achieved to date 

where Z = the greater of zero or [(Total Sublicensee Revenues) - (2 x Medarex Fees achieved)] x [0.175]. 

Examples of the application of clause (y) and the reconciliation mechanism to various scenarios are set forth in Exhibit C. 

In the event that the reconciliation shows that Medarex has received more than it is entitled to under the above formula, FibroGen may either offset such
amount against other future payments Medarex is to receive under this subsection (b) or require Medarex to remit the excess cash or equity, whichever form the original payment was made, unless Medarex has already sold the equity in which case
Medarex will remit the cash equivalent. FibroGen shall promptly remit any amounts owed to Medarex as a result of the reconciliation. To the extent that additional Medarex Fees still remain available for offset or may arise in the future under
Section 4.2 with respect to any Product, FibroGen may make the payment in respect of the Sublicensing Revenues in clause (y) in cash or equity consistent with the provisions of Section 4.4 (Equity) herein and Medarex shall have the
same rights relating to any equity acquired pursuant to clause (y) as set forth in Section 4.4. With respect to each Sublicensee, FibroGen shall notify Medarex of FibroGen’s election to pay to Medarex the amounts subject to clause
(i) or (ii) above within thirty (30) days after receipt of the first payment which would constitute a Sublicensee Revenue subject to (ii) above. Payments hereunder with respect to each Product shall be treated separately and not
offset against other amounts due between the parties unless otherwise agreed to by the parties. 
 (c) In addition to the above, in partial
consideration for the commercial license, with respect to diagnostic Products, FibroGen shall pay to Medarex, at FibroGen’s option, either (i) a royalty of ten percent (10%) on annual Net Sales by Sublicensees of FibroGen and its 

  
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 Affiliates of Products sold as diagnostics, on a Product-by-Product basis and no portion of Sublicensee
Revenues, or (ii) seventeen and one-half percent (17.5%) of (x) all payments of royalties received by FibroGen and/or its Affiliates in respect of the sale by a Sublicensee of any Products sold as diagnostics, and (y) all
Sublicensee Revenues relating to diagnostic Products or rights thereto received from such Sublicensee. With respect to each Sublicensee, FibroGen shall notify Medarex of FibroGen’s election to pay to Medarex the amounts subject to clause
(i) or (ii) above within thirty (30) days after receipt of the first payment which would constitute a Sublicensee Revenue subject to (ii) above. 

(d) In addition to the foregoing, FibroGen shall also reimburse Medarex for the amount of any royalties paid by Medarex to Medical Research
Council (MRC) and required by the October 1, 1993 License Agreement between GenPharm International and MRC in connection with the sale of any Products by FibroGen, Affiliates or Sublicensees; provided, however, that in no event shall the
reimbursement by FibroGen to MRC be increased beyond those required in the October 1, 1993 License Agreement between MRC and GenPharm International, Inc. without FibroGen’s written consent. At the request of FibroGen, Medarex shall request
MRC to grant FibroGen a sublicense on substantially similar terms as set forth in its license with MRC. 
 (e) It is understood and agreed
that pursuant to that certain license agreement entered by GenPharm International, Inc. and DNX, dated January 1, 1991 (the “DNX License”) that Medarex may be obligated to pay to DNX a percentage of royalties received by Medarex from
FibroGen with respect to the sale of Products, and Medarex agrees to pay to DNX amounts received from FibroGen which are consistent with such agreement. Medarex further agrees that the amounts it pays to DNX with respect to amounts received from
other licensees of the applicable technology shall be treated consistently. In the event that in any litigation or other binding arbitration between Medarex and DNX regarding the DNX License, a final determination is made (which is not appealed or
appealable, unless Medarex elects not to appeal) that the royalties due DNX under the DNX License should be based on any amount other than the amounts received by Medarex from a licensee (e.g., FibroGen), then in addition to any other amounts due to
Medarex pursuant to this Agreement, FibroGen shall be responsible for paying to Medarex (for all past and future sales of Products) amounts equal to the amounts due pursuant to the interpretation of the DNX License as determined in the litigation or
other binding arbitration, as applied to the Products subject to the licenses granted hereunder. It is understood and agreed that Medarex may, but shall have no obligation to, appeal any holding in any litigation or binding arbitration. 

4.3.2 Combination Products. In the event that a Product is sold in combination with one or more other product(s) which is not a
product, Net Sales from such sales for purposes of calculating the amounts due under Section 4.3.1 above shall be calculated by multiplying the Net Sales of that combination by the fraction A/(A + B), where A is the gross selling price of the
Product sold separately and B is the gross selling price of the other product sold separately. In the event that no such separate sales are made by FibroGen, Net Sales for royalty determination shall be as agreed 

  
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 CONFIDENTIAL 

 

 
by FibroGen and Medarex, based upon the relative importance and proprietary protection of the Product and other product. 

4.3.3 Royalty Reduction. In a country where there are no patent applications or patents within the Medarex Technology, and no patent
applications or patents within the FibroGen Technology covering a particular Product, and in such country there are commercially significant sales of a competing product which contains a monoclonal antibody that has been or becomes approved by the
applicable regulatory authority for treatment of the same indication as the applicable Product, then the royalty due to Medarex pursuant to Section 4.3.1 with respect to Net Sales of the applicable Product in such country shall be reduced by
one-half (1/2). 
 4.3.4 Royalty Term. The royalties due pursuant to this Section 4.3 shall be payable on a Product-by-Product
and country-by-country basis in each country as follows: (i) in countries where there are no patent applications or patents within the Medarex Technology and no patent application or patent within the FibroGen Technology covering a particular
Product, until ten (10) years following the first commercial sale of such a Product in such country, and (ii) in countries where there are one or more patent applications or patents within the Medarex Technology, or one or more patent
applications or patents within the FibroGen Technology covering such a Product, until the expiration of the last to expire patent within the Medarex Technology or FibroGen Technology covering the applicable Product in such country. 

4.3.5 Trade Secrets. The parties acknowledge and agree that a principal value contributed by Medarex is access to the Mice and Mice
Materials allowing accelerated time to market and enhanced probability of success, and that Medarex may not own or control patents that cover the manufacture, sale or use of a particular Product. FibroGen acknowledges and agrees that a principal
value FibroGen receives hereunder is in such access, and accordingly FibroGen shall reimburse the amounts paid by Medarex pursuant to Section 4.3.1(d) and (e) and pay the royalties at the rates specified in Sections 4.3.1(a), (b) and
(c) and 4.3.2 during the term as set forth in Section 4.3.4, regardless of whether the applicable Product is covered by a patent application or patent within the Medarex Technology or FibroGen Technology. 

4.4 Equity. 
 4.4.1
Pre-IPO. 
 (a) At FibroGen’s election, the commercial license payments and milestone payments may be paid in FibroGen common
stock, preferred stock or cash. To the extent that FibroGen acquires a commercial license pursuant to Section 4.1 or achieves a milestone subject to Section 4.2 prior to becoming a public company, the FibroGen stock shall be valued at the
price of the most recent financing of FibroGen which involved an investment of at least three million dollars ($3,000,000). For purposes of determining FibroGen’s market valuation in connection with such 

  
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 financing, FibroGen shall be deemed to have a market valuation equal to the greater of (i) eighty
million dollars ($80,000,000), or (ii) if such financing was at a market valuation over eighty million dollars ($80,000,000), the actual pre-money market valuation of FibroGen in such financing. 

(b) If, subsequent to the financing of FibroGen referenced in Section 4.4.1(a) above, FibroGen Europe, Ltd. engages in a public offering
of its stock, then the value of FibroGen stock shall be adjusted to take into account the value of FibroGen’s interest in FibroGen Europe, Ltd. and the current trading price of FibroGen Europe, Ltd. stock. For purposes of this Section, FibroGen
Europe’s collagen program shall be assumed to be worth one-fifth (1/5) of FibroGen on a consolidated basis when wholly-owned. (For example, if the FibroGen initial valuation was eighty million dollars ($80,000,000) and FibroGen Europe had
a valuation of sixteen million dollars ($16,000,000), if FibroGen Europe goes public and has a one hundred million dollar ($100,000,000) market valuation and FibroGen owns fifty percent (50%) of FibroGen Europe, the adjusted valuation for
FibroGen would be one hundred fourteen million dollars ($114,000,000) (i.e., $80M - $16M + 50% ($100M)). 
 4.4.2 Post-IPO.

 (a) Once FibroGen becomes a public company, any milestone payments paid in equity from that point forward, as long as FibroGen remains a
public company, will be paid in fully registered shares or unregistered shares based upon the average of the high and low trading prices of FibroGen’s stock within ninety (90) business days prior to the date payment is due. 

(b) Subsequent to FibroGen’s initial public offering (“IPO”), for any unregistered shares that Medarex has acquired from
FibroGen within one (1) year prior to FibroGen’s IPO or thereafter, if Medarex sells any such shares of FibroGen’s common stock in a private transaction at a loss from the initial issuance valuation (at the time Medarex received its
shares) after taking into account any transactions costs and fees, FibroGen shall reimburse Medarex for such losses, up to a maximum of fifteen percent (15%) of the initial issuance valuation of such shares. However, prior to executing any such
private transaction, Medarex shall notify FibroGen of the contemplated sale, and the terms thereof, and FibroGen shall notify Medarex within fourteen (14) days thereafter if it chooses to effectuate and file a registration of Medarex’s
shares, which registration shall be effective within five (5) months of the date of Medarex’s notice rather than reimbursing Medarex for any losses from the proposed private sale. FibroGen shall promptly notify Medarex of such
registration. FibroGen’s obligation to reimburse Medarex for any loss from the private sale shall only exist with respect to the shares acquired prior to the initial public offering for a period of twelve (12) months after the public
offering and with respect to the shares acquired after the initial public offering for a period of twelve (12) months thereafter; provided, the reimbursement period shall be further extended for the period of any lock-up period imposed on
Medarex pursuant to Section 4.4.2(c). Moreover, if FibroGen notifies Medarex as provided above that FibroGen intends to effectuate a registration of shares within five (5) months, but fails to do so, then if 

  
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 CONFIDENTIAL 

 

 Medarex sells any shares of FibroGen’s common stock (which were to be subject to the registration) in a
private transaction at a loss from the initial issuance valuation (at the time Medarex received its shares) after taking into account any transactions costs and fees, FibroGen shall reimburse Medarex for such losses up to a maximum of twenty-five
percent (25%) of the initial issuance valuation of such shares. 
 (c) Medarex shall agree to any lock-up period that may be required
by underwriters in connection with an initial public offering as long as the officers, directors and affiliates (other than the Finnish government or SITRA or funds related thereto) of FibroGen are subject to similar restrictions. For purposes of
this subsection (c) only, an “affiliate” shall be deemed to be a holder of ten percent (10%) or more of FibroGen’s outstanding voting stock. 

4.4.3 Recalculation. 

(a) If FibroGen completes a public offering at a price which establishes a market valuation for FibroGen less than eighty million dollars
($80,000,000), .then any payments to Medarex hereunder based upon a market capitalization of FibroGen of eighty million dollars ($80,000,000) or more pursuant to Section 4.4.1(ii) shall be recalculated based upon the market valuation of
FibroGen determined by the public offering price and Medarex shall be entitled to the incremental additional shares which Medarex would have received had the prior payment(s) been calculated on the basis of a market valuation determined by the
public offering price based on the average of the high and low trading prices of FibroGen’s stock within ninety (90) business days prior to the date of payment. 

(b) In the event that FibroGen restructures its business into one or more entities and if Medarex is entitled to receive a proportionate
interest in the spun off entity, then the value of the payments pursuant to Sections 4.4.1 and 4.4.2 above shall be considered the aggregate of the value of the stock of the spun off entity and the value of the FibroGen stock; provided, however,
that in the case that FibroGen is a public company and the spun off entity (the “New Entity”) is a private company, Medarex shall only receive subsequent license or milestone equity payments in the form of the public company stock, valued
without regard to the New Entity. 
  

	5.	PAYMENTS 

 5.1 Timing of Royalty Payments. All royalties due to Medarex shall be
paid within sixty (60) days after the last day of the calendar quarter in which they accrue. 
 5.2 Payment Method. All amounts
due Medarex hereunder shall be paid in U.S. dollars by wire transfer in immediately available funds to an account designated by Medarex. 

  
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 5.3 Currency: Foreign Payments. If any currency conversion shall be required in
connection with the payment of any royalties hereunder, such conversion shall be made by using the exchange rate for the purchase of U.S. dollars reported by the Chase Manhattan Bank on the last business day of the calendar quarter to which such
royalty payments relate. If at any time legal restrictions prevent the prompt remittance of any royalties owed on Net Sales in any jurisdiction, FibroGen may notify Medarex and make such payments by depositing the amount thereof in local currency in
a bank account or other depository in such country in the name of Medarex, and FibroGen shall have no further obligations under this Agreement with respect thereto. 

5.4 Taxes. All royalty amounts required to be paid to Medarex pursuant to this Agreement may be paid with deduction for withholding for
or on account of any taxes (other than taxes imposed on or measured by net income) or similar governmental charge imposed by a jurisdiction other than the United States (“Withholding Taxes”). At Medarex’s request, FibroGen shall
provide Medarex a certificate evidencing payment of any Withholding Taxes hereunder and shall reasonably assist Medarex to obtain the benefit of any applicable tax treaty. 
  

	6.	REPORTS AND RECORDS 

 6.1 Royalty Reports. FibroGen shall deliver to Medarex
within sixty (60) days after the end of each calendar quarter in which Products are sold a report setting forth in reasonable detail the calculation of the royalties payable to Medarex for such calendar quarter, including the Products sold in
each country by FibroGen and its Sublicensees, the Net Sales thereof, and all amounts received from Sublicensees for sales of Products. Such reports shall be Confidential Information of FibroGen subject to Article 9 herein. 

6.2 Inspection of Books and Records. FibroGen shall maintain accurate books and records which enable the calculation of royalties
payable hereunder to be verified. FibroGen shall retain the books and records for each quarterly period for three (3) years after the submission of the corresponding report under Section 5.1 hereof. Upon thirty (30) days prior notice
to FibroGen, independent accountants selected by Medarex, may have access to FibroGen’s books and records during FibroGen’s normal business hours to conduct a review or audit, for the purpose of verifying the accuracy of FibroGen’s
payments and compliance with this Agreement. Any such inspection or audit shall be at Medarex’s expense, however, in the event an inspection reveals underpayment of five percent (5%) or more in any audit period, FibroGen shall pay the
costs of the inspection and promptly pay to Medarex any underpayment with interest from the date such amount(s) were due, at the prime rate reported by the Chase Manhattan Bank, New York, New York plus two percent (2%). 

 

	7.	OTHER OBLIGATIONS 

 7.1 Reports to Medarex. During the term of this Agreement,
FibroGen shall keep Medarex reasonably informed of its activities subject to this Agreement, including without 

  
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 limitation, the commercialization of Products, and annually shall provide Medarex with a written report
detailing such events and activities. When the registration package requesting approval for commercial sale of the Product is first filed in the U.S., the European Union and Japan, and in each case when approval is received therefor, FibroGen will
promptly notify Medarex in writing. 
 7.2 Reports to FibroGen. During the term of this Agreement, Medarex shall keep FibroGen
reasonably informed of the status of Medarex’s patent applications and patents relating to the Patent Rights, any amendments to the Cross-License and information pertaining to the exclusivity of the rights granted hereunder. 

7.3 Regulatory Filings. FibroGen shall submit registration packages requesting approval for commercial sale of the Product as soon as
reasonably practicable. FibroGen (or its designee) shall file and hold title to all regulatory applications, approvals and supplements thereto. Medarex will provide the necessary documentation for any regulatory filings relating to the Mice,
Antibodies and hybridoma cell line delivered to FibroGen and any other assistance with respect to regulatory filings or agencies as may be reasonably requested by FibroGen at FibroGen’s expense. 

7.4 Abandoned Products. FibroGen shall promptly notify Medarex should it elect to, abandon its rights to pursue commercialization of
any Product in any country. Such notice will effectuate FibroGen’s voluntary abandonment of its right hereunder to market the Product in such country; provided, the abandonment of the Product in any particular country hereunder shall not be
construed to be a termination of this Agreement with respect to the other countries or Products. 
  

	8.	CONFIDENTIALITY 

 8.1 Confidential Information. Except as expressly provided
herein, the parties agree that, for the term of this Agreement and for five (5) years thereafter, the receiving party shall keep completely confidential and shall not publish or otherwise disclose and shall not use for any purpose except for
the purposes contemplated by this Agreement any Confidential Information furnished to it by the disclosing party hereto pursuant to this Agreement, except that to the extent that it can be established by the receiving party by competent proof that
such Confidential Information: 
 (i) was already known to the receiving party, other than under an obligation of confidentiality, at the
time of disclosure; 
 (ii) was generally available to the public or otherwise part of the public domain at the time of its disclosure to
the receiving party; 
 (iii) became generally available to the public or otherwise part of the public domain after its disclosure and other
than through any act or omission of the receiving party in breach of this Agreement; 

  
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 (iv) was independently developed by the receiving party as demonstrated by documented
evidence prepared contemporaneously with such independent development; or 
 (v) was subsequently lawfully disclosed to the receiving party
by a person other than a party hereto. 
 8.2 Permitted Use and Disclosures. Each party hereto may use or disclose information
disclosed to it by the other party to the extent such use or disclosure is reasonably necessary in complying with applicable governmental regulations or otherwise submitting information to tax or other governmental authorities, conducting clinical
trials, or making a permitted sublicense or otherwise exercising its rights hereunder, provided that if a party is required to make any such disclosure of another party’s confidential information, other than pursuant to a confidentiality
agreement, it will give reasonable advance notice to the latter party of such disclosure and, save to the extent inappropriate in the case of patent applications, will use its reasonable efforts to secure confidential treatment of such information
prior to its disclosure (whether through protective orders or otherwise). 
 8.3 Public Disclosure. Except as otherwise required by
law (without consideration of contractual obligations to third parties), neither party shall issue a press release or make any other public disclosure of the terms of this Agreement without the prior approval of such press release or public
disclosure. Each party shall submit any such press release or public disclosure to the other party, and the receiving party shall promptly review such press release or public disclosure, but in no event more than fifteen (15) days to review and
approve any such press release or public disclosure, which approval shall not be unreasonably withheld. If the receiving party does not respond within such fifteen (15) day period, the press release or public disclosure shall be deemed
approved. In addition, if a public disclosure is required by law, including without limitation in a filing with the Securities and Exchange Commission, the disclosing party shall provide copies of the disclosure reasonably in advance of such filing
or other disclosure for the nondisclosing party’s prior review and comment. Upon execution of this Agreement, the parties shall agree to a redacted version of this Agreement to be used for any and all submissions permitted under this Section
unless otherwise agreed by the parties in writing or required to comply with law. 
 8.4 Confidential Terms. Except as expressly
provided herein, each party agrees not to disclose any terms of this Agreement to any third party without the consent of the other party; provided, with prior notice to the other party, disclosures may be made as required by securities or other
applicable laws, or to a party’s accountants, attorneys and other professional advisors. 
  

	9.	REPRESENTATIONS AND WARRANTIES 

 9.1 Medarex. Medarex represents and warrants
that: (i) it is a corporation duly organized validly existing and in good standing under the laws of the State of New Jersey; (ii) the execution, 

  
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 delivery and performance of this Agreement have been duly authorized by all necessary corporate action on the
part of Medarex; (iii) it is the sole and exclusive owner of all right, title and interest in the Mice; (iv) it has the right to grant the rights and licenses granted herein; (v) as of the Effective Date, to the best knowledge of
Medarex, there are no issued U.S., EPO or Japanese patents owned by third parties which would be infringed by the use of the Mice to make Antibodies or hybridoma cells producing said Antibodies in connection with practice of the licenses granted
herein; (vi) as of the Effective Date, Medarex has not provided a third party licensee of the Patent Rights a broader representation and warranty regarding non-infringement of the patent rights of a third party due to the use of the Mice than
the representation in clause (v) above; and (vii) as of March 31, 1998, to the best knowledge of Medarex, (a) there have been no opposition proceedings filed against any Australian patent applications within the Medarex
Technology, and Medarex has not participated in any opposition proceedings filed against any Australian patent applications owned by third parties which, if such application became an issued patent, would be infringed by the use of the Mice to make
Antibodies or hybridoma cells producing said Antibodies in connection with practice of the licenses granted herein, and (b) there are no issued Canadian patents within the Medarex Technology, and Medarex has not participated in any
re-examination proceedings of any Canadian patents owned by third parties which would be infringed by the use of the Mice to make Antibodies or hybridoma cells producing said Antibodies in connection with the practice of the licenses granted herein.

 9.2 FibroGen. FibroGen represents and warrants that: (i) it is a corporation duly organized validly existing and in good
standing under the laws of the State of Delaware; and (ii) the execution, delivery and performance of this Agreement have been duly authorized by all necessary corporate action on the part of FibroGen. 

9.3 Disclaimer of Warranties. THE MICE ARE PROVIDED “AS IS”, AND EXCEPT AS OTHERWISE EXPRESSLY SET FORTH IN THIS AGREEMENT,
MEDAREX AND ITS RESPECTIVE AFFILIATES MAKE NO REPRESENTATIONS AND EXTEND NO WARRANTIES OR CONDITIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED, WITH RESPECT TO THE MICE, ANTIBODIES, PRODUCTS OR MEDAREX TECHNOLOGY, INCLUDING, BUT NOT LIMITED TO,
WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE, VALIDITY OF THE PATENT RIGHTS LICENSED HEREUNDER, OR NONINFRINGEMENT OF THE INTELLECTUAL PROPERTY RIGHTS OF THIRD PARTIES. 

9.4 Disclaimer. Except as otherwise expressly set forth in this Agreement, nothing in this Agreement is or shall be construed as: 

 

	 	(a)	A warranty or representation by Medarex as to the validity or scope of any claim or patent within the Patent Rights; 

  
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	 	(b)	A warranty or representation that anything made, used, sold, or otherwise disposed of under any license granted in this Agreement is or will be free from infringement of any patent rights or other intellectual property
right of any third party; 

  

	 	(c)	An obligation to bring or prosecute actions or suits against third parties for infringement of any of the Patent Rights; or 

  

	 	(d)	Granting by implication, estoppel, or otherwise any licenses or rights under patents or other rights of Medarex or third parties, regardless of whether such patents or other rights are dominant or subordinate to any
patent within the Patent Rights. 

 9.5 Further Commitment. Following the date hereof, if Medarex provides to a third
party a warranty or indemnity that the use of the Mice to make antigen-specific antibodies, or hybridoma cells producing such antigen-specific antibodies, will not (whether qualified by Medarex’s knowledge or not) infringe published PCT patent
applications, then Medarex shall notify FibroGen and provide to FibroGen a further representation and warranty and/or indemnity comparable in scope to the warranty and/or indemnity provided to the third party, effective as of the date of such third
party agreement. 
  

	10.	INTELLECTUAL PROPERTY 

 10.1 Patent Rights. If FibroGen acquires a commercial
license, FibroGen shall have the sole right, but not the obligation, at its expense, to prepare, file, prosecute and maintain (i) patent applications and patents within the FibroGen Technology, and (ii) patent applications and patents
within the Patent Rights included in the Medarex Technology, provided (a) such patent applications and/or patents relate solely to Antibodies or Products subject to this Agreement, and (b) are subject to a commercial license to FibroGen
granted hereunder, in countries selected by FibroGen, and for conducting any interferences, reexaminations, reissues, oppositions, or request for patent term extension relating thereto. 

10.2 Failure to Prosecute. In the event that FibroGen declines to file or, having filed, declines to further prosecute and maintain any
patent applications or patents subject to Section 10.1 above, FibroGen shall provide Medarex notice thereof prior to the expiration of any deadline relating to such activities, as much in advance as practicable, but in any event at least ten
(10) days prior notice, and Medarex shall have the right to file, prosecute and maintain such patent applications or patents in the name of FibroGen, at Medarex’s expense, using counsel of its choice. 

10.3 Cooperation. Medarex shall be given an opportunity to review FibroGen’ activities pursuant to Section 10.1 and provide
input thereto. FibroGen shall consider in good faith any 

  
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 request by Medarex to include in such patent applications such claims as Medarex may request. FibroGen shall
keep Medarex fully informed as to the status of such patent matters, including, without limitation, by providing Medarex the opportunity, at Medarex’s expense, to review and comment on any documents relating to FibroGen Technology which will be
filed in any patent office as much in advance as practicable, but at least ten (10) days before such filing, and promptly providing Medarex copies of any documents relating to FibroGen Technology which FibroGen receives from such patent
offices, including notice of all interferences, reissues, reexaminations, oppositions or requests for patent term extensions. 
 10.4
Infringement Claims. If the manufacture, importation, sale or use of the Product pursuant to this Agreement results in any claim, suit or proceeding alleging patent infringement against Medarex or FibroGen, such party shall promptly notify
the other party hereto, and if the notified party has an obligation to indemnify the other party pursuant to Section 12.1 or 12.2, such party shall have the right to control the defense of such claim, suit or proceeding. The defendant shall
keep the other party hereto reasonably informed of all material developments in connection with any such claim, suit or proceeding. FibroGen shall have the sole right, but not the obligation, to prosecute any infringement of the FibroGen Technology,
at its expense. Financial recovery from any litigation will first be applied to reimburse FibroGen for its litigation expenditures and any remaining amounts shall be subject to the royalty provisions of Section 4.3.1. 

10.5 Interference. The parties agree to use good faith efforts to resolve any interference proceeding which is declared by the U.S.
Patent and Trademark Office between patent applications or patents owned by Medarex and FibroGen because of claims subject to Sections 2.7.2(b) and (c) above. In the event that the parties are unable to amicably resolve such an interference
within thirty (30) days of the declaration of interference, the parties shall submit their dispute to mediation for the sole purpose of determining all issues that may be raised in an interference proceeding, and promptly settling such disputes
so as to effectuate the intention of the parties set forth in this Agreement. The mediation shall be conducted pursuant to the then-current Commercial Mediation Rules of the American Arbitration Association in Palo Alto, California by an independent
patent attorney agreed to by the parties. The cost of any mediation, including administrative fees of the arbitrator, shall be shared equally by the parties. Each party shall bear the cost of its own attorneys’ fees and expert fees. The
decision and/or award rendered by the mediator shall be written, final and non-appealable and may be entered in any administrative body or court of competent jurisdiction. The parties agree that, any provision of applicable law notwithstanding, they
will not request, and the mediator shall have no authority to award, punitive or exemplary damages against any party. 
 10.6 Further
Obligations Regarding Research Inventions. 
 10.6.1 Claiming Priority. If Medarex wishes to file a patent application with
respect to a Research Invention and claim filing priority for such patent application based on an earlier filed application having a priority date on or before October 21, 1997, it shall notify FibroGen. FibroGen 

  
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 shall have the right, only to be exercised reasonably, to preclude Medarex from such priority claim for
claims to antibodies directed to an Antigen (i.e., any antibody directed to CTGF for the treatment of fibrosis) which (a) do not recite specific DNA or protein sequences, or (b) FibroGen reasonably believes are not otherwise Excluded
Claims. It is understood and agreed that FibroGen shall not have such a right for any Antibody claims which do recite specific DNA or protein sequences or for any other claims that FibroGen reasonably believes are Excluded Claims. 

10.6.2 Terminal Disclaimer. If Medarex wishes to file a terminal disclaimer in any patent application claiming a Research Invention,
and the patent or application with respect to which the terminal disclaimer is to be filed claims priority to a filing date on or before October 21, 1997, then it shall notify FibroGen. FibroGen shall have the right, only to be exercised
reasonably, to preclude Medarex from seeking such a terminal disclaimer if the terminal disclaimer would limit the term of any claims to antibodies directed to an Antigen which (a) do not recite specific DNA or protein sequences, or
(b) FibroGen reasonably believes are not otherwise Excluded Claims. It is understood and agreed that FibroGen shall not have such a right for any Antibody claims which do recite specific DNA or protein sequences or for any other claims that
FibroGen reasonably believes are Excluded Claims. 
 10.6.3 Filing or Adding Claims. In any patent application claiming a Research
Invention, if Medarex wishes to file or add any claim specifically regarding Antibodies that (a) does not recite specific DNA or protein sequences or (b) FibroGen reasonably believes is not otherwise an Excluded Claim, it shall notify
FibroGen. FibroGen shall have the right, only to be exercised reasonably, to preclude Medarex from filing or adding such claim if FibroGen reasonably believes it is not an Excluded Claim. It is understood and agreed that FibroGen shall not have such
a right with regard to any Antibody claims which do recite a specific DNA or protein sequence or for any other claims that FibroGen reasonably believes are Excluded Claims. 

10.6.4 Notice to Medarex. FibroGen may exercise its preclusion rights provided in Sections 10.6.1, 10.6.2 and 10.6.3 above by notice to
Medarex within thirty (30) days (except with respect to the adding of claims, in which case notice shall be limited to ten (10) business days) following receipt of notice from Medarex that it intends to (i) claim such a priority date,
(ii) file such a terminal disclaimer or (iii) file or add such a claim, as the case may be; provided that, with respect to Section 10.6.2 only, in the event that Medarex desires to file a terminal disclaimer on an expedited basis as a
consequence of an oral request to do so by the United States Patent and Trademark Office, then FibroGen shall use its best efforts to determine whether to exercise its preclusion rights pursuant to Section 10.6.2 within any expedited time frame
requested by the United States Patent and Trademark Office. 
 10.6.5 Data. 

  
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 (a) FibroGen shall have the right, only to be exercised reasonably, to preclude Medarex from
using or disclosing any data developed by Medarex relating to the structural or molecular characteristics of Antigens including, but not limited to, the relevant epitope(s), or any data developed by FibroGen in connection with the Research except to
the extent such data or information pertaining thereto is to be disclosed by Medarex in a patent application or the prosecution of a patent, and (v) was disclosed in a prior, or is to be disclosed in a simultaneous, patent application,
(w) constitutes DNA or protein sequence information, (x) constitutes assay results, if other results of the same or similar assays have been disclosed in a prior, or are to be disclosed in a simultaneous, patent application, (y) is
reasonably necessary to disclose the best mode of the claimed invention, or (z) constitutes deposit or enablement information, pursuant to Section 10.6.5(b) below. FibroGen may exercise such a preclusion right only after full disclosure to
Medarex of all data that is included in clause (v), (w), (x), (y) or (z). In the case of clause (w), (y) and (z), unless FibroGen provided the relevant data to Medarex specifically pursuant to subSections 10.6.5(a) or (b), Medarex shall
send FibroGen written notice of the intent to disclose the data and the form of disclosure at least fifteen (15) business days prior to the disclosure. 

(b) For purposes of this Section, “data” shall include, without limitation, information relating to any deposit made of any cell
line. If FibroGen has not made such .a deposit, if required by applicable law, Medarex may deposit a particular cell line, in a recognized international depository; provided, before making such a deposit, Medarex shall notify FibroGen, identifying
the cell line which it intends to deposit. If FibroGen does not wish Medarex to make such a deposit, it shall notify Medarex within ten (10) business days of Medarex’s notice and provide Medarex with data reasonably necessary to establish
enablement for purposes of patentability, and Medarex shall not make the deposit but shall have the right to use such data to establish enablement. 

10.7 Patent Extensions. If FibroGen acquires a commercial license with respect to any issued patent claiming a Research Invention
directed to (i) one or more compositions of matter (i.e., an Antibody), except formulations of Antibodies for therapeutic use, or (ii) one or more methods of production, then, so long as FibroGen retains a commercial license hereunder,
unless a prior extension has been obtained with regard to the applicable patent, Medarex designates FibroGen or its designee as its agent for obtaining an extension of such patent or governmental equivalent which extends the exclusivity of the
patent where available in any country in the world, or if not feasible, at Medarex’s option, permit FibroGen to file in Medarex’s name or diligently obtain such extension for FibroGen, its Affiliate(s) or Sublicensee(s), at FibroGen’s
expense. Furthermore, Medarex agrees to provide reasonable assistance, at no out-of-pocket expense, to facilitate FibroGen’s efforts to obtain any extension. If for any reason FibroGen or its designee fails to exercise diligent efforts to
obtain an extension or determines that it will not seek such an extension, Medarex shall have the right to undertake such activities and FibroGen shall provide reasonable assistance, at no out-of-pocket expense, to facilitate Medarex’s efforts
to obtain any such extension. 

  
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 10.8 Reimbursement. If FibroGen (i) is assigned a patent application or patent
pursuant to this Agreement, or (ii) acquires a commercial license under this Agreement to any patent application or patent, or (iii) acquires a non-exclusive license pursuant to Section 3.2 to patent applications and patents within
the Medarex Technology and commercializes a product within the scope of such license for which it has no royalty obligations to Medarex hereunder, in each case (i.e., under (i), (ii) or (iii) above), which patent application or patent
which relates solely to Antibodies licensed hereunder, and/or Products, and/or the making and/or use of any of the preceding, then FibroGen shall reimburse Medarex for all costs and expenses incurred by Medarex in connection with the preparation,
filing, prosecution, maintenance, enforcement and/or defense of such patent applications and patents; provided, any such reimbursement shall be on a pro-rata basis, calculated based on the number of other licensees of such patent application(s) or
patent(s). FibroGen shall pay any such amounts to Medarex within thirty (30) days of an invoice therefore. 
  

	11.	DISPUTE RESOLUTION 

 11.1 Mediation. If a dispute arises out of or relates to this
Agreement, or the breach thereof, and if said dispute cannot be settled through negotiation, the parties agree first to try in good faith to settle the dispute by mediation under the Commercial Mediation Rules of the American Arbitration
Association, before resorting to arbitration, litigation, or some other dispute resolution procedure. 
  

	12.	INDEMNIFICATION 

 12.1 Medarex. Medarex shall indemnify, defend and hold harmless
FibroGen and its directors, officers and employees (each a “FibroGen Indemnitee”) from and against any and all liabilities, damages, losses, costs or expenses (including attorneys’ and professional fees and other expenses of
litigation and/or arbitration) (a “Liability”) resulting from a claim, suit or proceeding made or brought by a third party against an FibroGen Indemnitee arising from or occurring as a result of (i) any breach of the representations
and warranties set forth in Section 9.1, or (ii) the conduct of the Research, except to the extent caused by the negligence or willful misconduct of FibroGen. 

12.2 FibroGen. FibroGen shall indemnify, defend and hold harmless Medarex and its directors, officers and employees (each a
“Medarex Indemnitee”) from and against any and all liabilities, damages, losses, costs or expenses (including attorneys’ and professional fees and other expenses of litigation and/or arbitration) (a “Liability”) resulting
from a claim, suit or proceeding made or brought by a third party against a Medarex Indemnitee, arising from or occurring as a result of (i) any breach of the representations and warranties set forth in Section 9.2, (ii) the conduct
of the Research or the practice by FibroGen of any right granted herein, or (iii) any development, testing, manufacture, importation, use, offer for sale, sale or other distribution of any Product by FibroGen or its Affiliates or Sublicensees
(including, without limitation, product liability claims), except in each case, (a) to the extent caused by the negligence or willful misconduct of Medarex, or (b) to the extent 

  
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 that any infringement claim brought by a third party is expressly based on the use of the Mice to make
Antibodies or hybridoma cells producing said Antibodies delivered to FibroGen; provided, however, that with respect to clause (b), the exclusion from FibroGen’s indemnity obligation with respect to the use of the Mice to make hybridoma cells
producing said Antibodies relates only to the basic hybridoma technology and not to any hybridoma relating to one or more of the specific Antigens. 

12.3 Procedure. In the event that any Indemnitee intends to claim indemnification under this Article 12 it shall promptly notify the
other party (the “Indemnitor”) in writing of such alleged Liability. The Indemnitor shall have the sole right to control the defense and settlement thereof. The Indemnitees shall cooperate with the Indemnitor and its legal representatives
in the investigation of any action, claim or liability covered by this Article 12. The Indemnitee shall not, except at its own cost, voluntarily make any payment or incur any expense with respect to any claim or suit without the prior written
consent of the Indemnitor, which the Indemnitor shall not be required to give. 
  

	13.	TERM AND TERMINATION 

 13.1 Term. The term of this Agreement shall commence on the
date hereof. Unless earlier terminated as provided in this Article 13, this Agreement shall continue in full force and effect on a country-by-country and Product-by-Product basis until there are no remaining royalty payment obligations in a country,
at which time the Agreement shall expire in its entirety in such country. 
 13.2 Termination for Cause. Either party may terminate
this Agreement in the event the other party has materially breached or defaulted in the performance of any of its obligations hereunder, and such default has continued for ninety (90) days after written notice thereof was provided to the
breaching party by the nonbreaching party. Any termination shall become effective at the end of such ninety (90) day period unless the breaching party has cured any such breach or default prior to the expiration of the ninety (90) day
period. Notwithstanding the above, in the case of a failure to timely pay any amounts due hereunder, the period for cure of any subsequent default following notice thereof shall be ten (10) days and, unless payment is made within such period
the termination shall become effective at the end of such period. 
 13.3 Termination for Insolvency. If voluntary or involuntary
proceedings by or against a party are instituted in bankruptcy under any insolvency law, or a receiver or custodian is appointed for such party, or proceedings are instituted by or against such party for corporate reorganization or the dissolution
of such party, which proceedings, if involuntary, shall not have been dismissed within sixty (60) days after the date of filing, or if such party makes an assignment for the benefit of creditors, or substantially all of the assets of such party
are seized or attached and not released within sixty (60) days thereafter, the other party may immediately terminate this Agreement effective upon notice of such termination. 

  
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 13.4 Permissive Termination. 

13.4.1 FibroGen. FibroGen may terminate the Research and/or this Agreement with forty-five (45) days written notice to Medarex.

 13.4.2 Medarex. In that event that FibroGen fails to obtain a commercial license pursuant to Section 3.1 on or before the end
of the Research Period, Medarex may terminate the Agreement with written notice to FibroGen. 
 13.5 Effect of Termination, Expiration or
Completion of Research. 
 (a) Accrued Rights and Obligations. Termination of this Agreement for any reason shall not release any
party hereto from any liability which, at the time of such termination, has already accrued to the other party or which is attributable to a period prior to such termination nor preclude either party from pursuing any rights and remedies it may have
hereunder or at law or in equity with respect to any breach of this Agreement. It is understood and agreed that monetary damages may not be a sufficient remedy for any breach of this Agreement and that the non-breaching party may be entitled to
injunctive relief as a remedy for any such breach. 
 (b) Return of Confidential Information. Upon any termination or expiration of
this Agreement, FibroGen and Medarex shall promptly return to the other party all Confidential Information of the other; provided counsel of each party may retain one (1) copy of such Confidential Information for archival purposes and for
ensuring compliance with Article 8. 
 (c) Stock on Hand. In the event this Agreement is terminated for any reason, FibroGen shall
have the right to sell or otherwise dispose of the stock of any Product subject to this Agreement then on hand, subject to Articles 5 and 6 until the first anniversary of the effective date of such termination. 

(d) Return of Mice and Mice Materials. Upon any termination of this Agreement, FibroGen shall promptly return to Medarex, or destroy
all hybridomas provided by Medarex and all cells capable of producing Antibodies, and in the event of such destruction an officer of FibroGen shall provide Medarex with written certification thereof. FibroGen shall be allowed to use any Antibodies
delivered to FibroGen during the Research in perpetuity but for research purposes only. Upon any termination or upon completion of the Research and unless otherwise permitted by FibroGen, Medarex shall (i) destroy the Mice, cells, Antibodies
and other biological materials resulting from the Research, and (ii) return any quantities of Antigen not used in connection with the Research to FibroGen. 

  
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 (e) Licenses. The option and license rights granted in Section 3.1 shall
terminate upon any termination of this Agreement, and in such event FibroGen and its Affiliates and Sublicensees shall cease all development and commercialization of Products. 

(f) Sublicenses. In the event of any termination pursuant to Section 13.3, Medarex agrees to grant to any party which is a
sublicensee of FibroGen as of the date of such termination a direct license under the Medarex Technology commensurate in scope with the sublicense granted by FibroGen, for consideration equal to the amounts due from FibroGen to Medarex under this
Agreement with respect to the activities of the sublicensee. 
 13.6 Survival. Sections 2.5 (with respect to Antibodies delivered to
FibroGen during the Research, to the extent permitted pursuant to Section 13.5(d) above), 2.6.3, 2.6.4, and 2.6.5(b) and (c) (with respect to the Antigens for which FibroGen is deemed to have exclusivity, and with respect to each Option
Antigen, on an Option Antigen-by-Option Antigen basis, if the requisite payments due under Section 2.6.3 and 4.1 have been made prior to the effective date of termination), 2.7, 3.2, 3.5, 13.5 and 13.6, and Articles 8, 9, 10, 11, 12 and 14 of
this Agreement shall survive termination of this Agreement for any reason. 
  

	14.	MISCELLANEOUS 

 14.1 Governing Law. This Agreement and any dispute, including
without limitation any arbitration, arising from the performance or breach hereof shall be governed by and construed and enforced in accordance with the laws of the state of California, without reference to conflicts of laws principles. 

14.2 Independent Contractors. The relationship of the parties hereto is that of independent contractors. The parties hereto are not
deemed to be agents, partners or joint venturers of the others for any purpose as a result of this Agreement or the transactions contemplated thereby. 

14.3 Assignment. This Agreement shall not be assignable by FibroGen to any third party hereto without the written consent of Medarex
which consent to a partial or entire assignment shall not be unreasonably withheld; except FibroGen may assign this Agreement, without such consent, to an entity that acquires all or substantially all of its business or assets to which this
Agreement pertains, whether by merger, reorganization, acquisition, sale, or otherwise. During the Research Period, Medarex may only assign this Agreement in connection with a merger, reorganization or sale of substantially all of Medarex’s
assets and with prior notice to FibroGen. After the Research Period, Medarex may assign this Agreement in connection with a merger, reorganization or sale of substantially all of Medarex’s assets, and may otherwise assign this Agreement to any
third party. Notwithstanding the foregoing, during or after the Research Period Medarex may not assign this Agreement (i) to Smith Klein Beechman, Glaxo Wellcome and Hoffman-LaRoche or any of their affiliates except in connection with a merger,
reorganization or sale of substantially all of Medarex’s 

  
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 assets, or (ii) to Japan Tobacco and any of its affiliates, regardless of the form of transaction,
including merger or operation of law. For purposes of this Section 14.3, an “affiliate” shall mean any corporation or other entity which is directly or indirectly controlling, controlled by or under the common control with the
relevant entity, and “control” shall mean the direct or indirect ownership of fifty percent (50%) or more of the outstanding shares or other voting rights of the subject entity to elect directors, or if not meeting the preceding, any
entity owned or controlled by or owning or controlling at the maximum control or ownership right permitted in the country where such entity exists. Notwithstanding the above, Medarex may assign its interest in the payments due to Medarex hereunder
to any party at any time. This Agreement shall be binding upon and inure to the benefit of the parties and their successors and assigns. 

14.4 Notices. All notices, requests and other communications hereunder shall be in writing and shall be personally delivered or sent by
telecopy or other electronic facsimile transmission or by registered or certified mail, return receipt requested, postage prepaid, in each case to the respective address specified below, or such other address as may be specified in writing to the
other parties hereto: 
  

			
	If to Medarex or GenPharm International:	  	  
 Medarex, Inc.
1545 Route 22 East
Annandale, NJ 08801
Attn:
President

		
	 If to FibroGen:
	  	FibroGen, Inc.
225 Gateway Boulevard
South San Francisco, CA 94080
Attn: President
cc: Corporate Counsel
phone: (650) 866-7200
facsimile: (650) 866-7201

 14.5 Force Majeure. Neither party shall lose any rights hereunder or be liable to the other party for
damages or losses (except for payment obligations) on account of failure of performance by the defaulting party if the failure is occasioned by war, strike, fire, Act of God, earthquake, flood, lockout, embargo, governmental acts or orders or
restrictions, failure of suppliers, or any other reason where failure to perform is beyond the reasonable control and not caused by the negligence, intentional conduct or misconduct of the nonperforming party has exerted all reasonable efforts to
avoid or remedy such force majeure; provided, however, that in no event shall a party be required to settle any labor dispute or disturbance. 

  
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 14.6 Injunctive Relief. Each party acknowledges that limitations and restrictions on
its possession and use of Mice, Mice Materials, Antibodies, Antigens and Confidential Information hereunder are necessary and reasonable to protect the other party, and expressly agrees that monetary damages would be inadequate to compensate such
party for any violation. The parties agree that any such violation would cause irreparable injury to the other party and agrees that without resorting to prior mediation or arbitration, and, in addition to any other remedies that may be available in
law, in equity or otherwise, the injured party shall be entitled to obtain temporary and permanent injunctive relief against any threatened violation of such limitations or restrictions or the continuation of any such violation in any court of
competent jurisdiction, without the necessity of proving actual damages or the posting of any bond. 
 14.7 Advice of Counsel.
Medarex and FibroGen have each consulted counsel of their choice regarding this Agreement, and each acknowledges and agrees that this Agreement shall not be deemed to have been drafted by one party or another and will be construed accordingly. 

14.8 Compliance with Laws. Each party shall furnish to the other party any information requested or required by that party during the
term of this Agreement or any extensions hereof to enable that party to comply with the requirements of any U.S. or foreign federal, state and/or government agency. 

14.9 Further Assurances. At any time or from time to time on and after the date of this Agreement, either party shall at the request of
the other party hereto (i) deliver to the requesting party any records, data or other documents consistent with the provisions of this Agreement, (ii) execute, and deliver or cause to be delivered, all such consents, documents or further
instruments of transfer or license, and (iii) take or cause to be taken all such actions, as the requesting party may reasonably deem necessary in order for the requesting party to obtain the full benefits of this Agreement and the transactions
contemplated hereby. 
 14.10 Export Controls. FibroGen agrees that it will take all actions necessary to insure compliance with all
U.S. laws, regulations, orders or other restrictions on exports and further will not sell, license or reexport, directly, or indirectly, the Product(s) to any person or entity for sale in any country or territory, if, to the knowledge of FibroGen
based upon reasonable inquiry, such sale, would cause the parties to be in violation of any such laws or regulations in effect at the time of such sale. FibroGen agrees to secure from any recipient of Product(s) adequate manually signed written
assurances prior to shipment from the United States as are required by the U.S. Export Regulations. 
 14.11 Severability. In the
event that any provisions of this Agreement are determined to be invalid or unenforceable by a court of competent jurisdiction, the remainder of the Agreement shall remain in full force and effect without said provision. In such event, the parties
shall in good faith negotiate a substitute clause for any provision declared invalid or unenforceable, which shall most nearly approximate the intent of the parties in entering this Agreement. 

  
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 14.12 Waiver. It is agreed that no waiver by either party hereto of any breach or
default of any of the covenants or agreements herein set forth shall be deemed a waiver as to any subsequent and/or similar breach or default. 

14.13 Complete Agreement. This Agreement, with its Exhibits, constitutes the entire agreement, both written and oral, between the
parties with respect to the subject matter hereof, and that all prior agreements respecting the subject matter hereof, either written or oral, expressed or implied, are merged and canceled, and are null and void and of no effect. No amendment or
change hereof or addition hereto shall be effective or binding on either of the parties hereto unless reduced to writing and duly executed on behalf of both parties. 

14.14 Use of Name. Neither party shall use the name or trademarks of the other party without the prior written consent of such other
party. 
 14.15 Headings. The captions to the several Sections and Articles hereof are not a part of this Agreement, but are included
merely for convenience of reference only and shall not affect its meaning or interpretation. 
 14.16 Counterparts. This Agreement
may be executed in two counterparts, each of which shall be deemed an original and which together shall constitute one instrument. 
 IN
WITNESS WHEREOF, Medarex and FibroGen have executed this Agreement by their respective duly authorized representatives. 
  

									
	MEDAREX, INC.	 		 	FIBROGEN, INC.
					
	By:	 	/s/ Michael Appelbaum	 		 	By:	 	/s/ Thomas B. Neff
					
	Print Name:	 	Michael Appelbaum	 		 	Print Name:	 	Thomas B. Neff
					
	Title:	 	Executive V.P.	 		 	Title:	 	CEO

  

			
	GENPHARM INTERNATIONAL, INC.
		
	By:	 	/s/ Michael Appelbaum
		
	Print Name:	 	Michael Appelbaum

  
 -32- 

 CONFIDENTIAL 

 

			
		
	Title:	 	President and C.O.O.

  
 -33- 

 EXHIBIT A 

ANTIGENS 
  

	1.	C-proteinase/bone-morphogenic protein 

	2.	M-tolloid 

	3.	M-tolloid-like (1) 

	4.	M-tolloid-like (2) 

	5.	N-proteinase 

	6.	Fibril assembly sequences 

	7.	Connective tissue growth factor (CTGF) 

	8.	CTGF receptor 

	9.	CTGF receptor and/or receptor conjugates which include the CTGF receptor 

	10.	An alternative ligand for the CTGF receptor to be named which has not been previously licensed to a third party by Medarex 

	11.	CTGF fragments 

	12.	An alternate CTGF or CCN homolog protein fragment 

 EXHIBIT B 
  

 

 EXHIBIT C 

Models—with offsets against commercial license, milestone payments and 1/2 the research support payments 

Scenario I: 
  

							
	 Sublicensee Non-royalty
Revenue Payments
	  	 FibroGen Share

(82 1⁄2%)
	  	 Medarex Share

(17 1⁄2%)
	  	 FG-Medx Contract Research support,
Commercial License Fee or
Milestones

		  		  		  	$.760M of quarterly pmts*
		  		  		  	$1.0M upon exercise of commercial license
	upfront fee - $5 million	  	$1.38 M* ((1/2 x $.76) + $1M)	  		  	—
		  	$2.987M (net total $2.607M = $1.38M + $2.987M—$1.76M)	  	$0.634M	  	
	Phase I - $2 million	  	$0.634	  	—	  	—
		  	$1.127	  	$0.239	  	
	Phase II - $5 million	  	$0.239 M	  	—	  	
		  	$3.928 M (net total $8.535M)	  	$.833 M (total $3.086**)	  	$1M (not paid b/c $3.086 > $2.38M)

  

	*	Assume the research period spans 8 quarters at $95,000 a quarter with a total of $760,000. The model only gives credit for  1⁄2
of these payments. 

	**	excludes  1⁄2 of the research payments of $380,000 in the total 

Model assumes termination during phase II which triggers the true up mechanism. 

True up calculation: 
  

					
	 Total sublicensee payments
	  	$	12 M	  
	 less 2 times (medx commercial fee, milestones achieved and  1⁄2 research support) ($2.38 x 2)
	  	 	($4.76M)	  
		  	  
	  
	 
		  	$	7.24 M	  
		  	 	x .175	  
		  	  
	  
	 
		  	$	1.267M	  
	 plus: Medx commercial fee, milestone achieved and
 1⁄2 research support
	  	$	2.38M	  
		  	  
	  
	 
	 Amount Medx is entitled to is
	  	$	3.647M	  
	 Amount paid to date**
	  	$	3.086M	  
		  	  
	  
	 
	 Amount due to Medx
	  	$	.561M	  

 After payment of $.561M to Medx, FG has received net $7.974 ($8.535–$.561) and Medx has received $4.027M ($3.647 +
$.380 of research support) 

 Scenario II: 
  

							
	 Sublicensee Non royalty

Revenue Payments
	  	 FibroGen Share

(82 1⁄2%)
	  	 Medarex Share

(17 1⁄2%)
	  	 FG-Medx Contract Research support,
Commercial License Fee or
Milestones

		  		  		  	$.760M of quarterly pmts*
		  		  		  	$1.0M upon exercise of commercial
	upfront fee - $5 million	  	$1.38 M *((1/2 x $.76) + $1M)	  		  	—
		  	 $2.987M
 (net total $2.607M)
	  	$0.634M	  	
	Phase I - $2 million	  	$0.634M	  	—	  	—
		  	$1.127 M	  	$.239 M	  	
	Phase II - $5 million	  	$0.239 M	  	—	  	
		  	 $3.928 M
 (net total $8.535)
	  	 $0.833 M
 (total $3.086M**)
	  	$1M (not paid b/c $3.086 > $2.38)
	Phase III - $2.5 million	  	$0.833M	  	—	  	 $2M ($1.002 paid b/c

$3.378< $4.38M)

		  	 $1.375
 (net total $10.743M)
	  	 $0.292M
 (total $3.378M**)
	  
	First BLA filing $2.5 million	  	 $1.294 M ($1.002M + $.292)
 $0.995

(net total $12.03M=
 $10.743-$1.002

+$1.294 +$0.995)
	  	 —
 $0.211

(total $4.591M**)
	  	$2M ($1.789 paid b/c $4.591<$6.38M)
	First BLA approval - $2.5 million	  	 $2 M ($1.789 +$.211)
 $0.413

(net total $12.654M)
	  	 —
 $0.088

(total $6.468M**)
	  	$4M ($3.912 paid b/c $6.468M< $10.38M)
	BLA approval in second market - $2.5 million	  	 $2.5M (add’l credit available of $1.5M)

(total (net))= $11.242)
	  	 —
 (total $10.38**)
	  	 $2M ($2M paid b/c $10.38<$12.38)

(total - $12.38M)

		  	 total (net) = $9.242
 ($11.242-$2M)
	  		  	

  

	*	Assume the research period spans 8 quarters at $95,000 a quarter with a total of $760,000. The model only gives credit for  1⁄2
of these payments. 

	**	excludes  1⁄2 of the research payments of $380,000 in the total 

True up calculation: 
  

					
	 Total sublicensee payments
	  	$	22M	  
	 less 2 times (medx commercial fee, milestones achieved and  1⁄2 research support) ($12.38 x 2)
	  	 	($24.76M)	  
		  	  
	  
	 
		  	 	($2.76)	  
		  	 	x .175	  
		  	  
	  
	 
	 the greater of zero or
	  	 	($.483)M	  
	 plus: Medx commercial fee, milestone achieved and
 1⁄2 research support
	  	$	12.38M	  
		  	  
	  
	 
	 Amount Medx is entitled to
	  	$	12.38	  
	 Amount paid to date**
	  	$	12.38	  
		  	  
	  
	 
	 Amount due to Medx
	  	$	0M	  

 FG has received net $9.242M and Medx has received $12.76M ($12.38M + $.380 of research support) 

Scenario III 
  

							
	 Sublicensee Non-royalty
Revenue Payments
	  	 FibroGen Share

(82 1⁄2%)
	  	 Medarex Share

(17 1⁄2%)
	  	 FG-Medx Contract Research support,
Commercial License Fee or
Milestones

		  		  		  	$.760 M of quarterly pmts*
		  		  		  	$1.0 M upon exercise of commercial
	upfront fee - $5 million	  	$1.38 M* ((1/2 x $.76) + $1M)	  		  	—
		  	 $2.987M
 (net total $2.607M)
	  	$0.634M	  	
	Phase I - $2 million	  	$0.634M	  	—	  	—
		  	$1.127 M	  	$.239M	  	
	Phase II - $5 million	  	$0.239 M	  	—	  	
		  	 $3.928 M
 (net total $8.535)
	  	 $0.833M
 (total $3.086M**)
	  	$1 M (not paid b/c $3.086 > $2.38)
	Phase III - $2.5 million	  	 $0.833M
 $1.375

(net total $10.743M)
	  	 —
 $0.292M

(total $3.378M**)
	  	 $2 M ($1.002 paid b/c
 $3.378< $4.38
M)

	First BLA filing $2.5 million	  	$1.294 M ($1.002M + $.292)	  	—	  	 $2 M ($1.789 paid b/c

$4.591<$6.38M)

		  	 $0.995
 (net total $12.03M= $10.743-$1.002
+$1.294 +$0.995)
	  	 $0.211
 (total $4.591M**)
	  
	First BLA approval - $2.5 million	  	 $2 M($1.789 +$.211)
 $0.413

(net total $12.654M)
	  	 —
 $0.088

(total $6.468M**)
	  	$4 M ($3.912 paid b/c $6.468M< $10.38M)
	BLA approval in second market - $2.5 million	  	 $2.5M (add’l credit available of $1.5M)

(total (net))= $11.242)
	  	 —
 —

(total $10.38**)
	  	 $2M ($2M paid b/c
 $10.38<$12.38)

(total - $12.38M)

	BLA approval in third market - $5 million	  	 $3.5 M
 $1.238 M

(net total $13.98M)
	  	 —
 $0.263M

(total $12.643M**)
	  	

  

	*	Assume the research period spans 8 quarters at $95,000 a quarter with a total of $760,000. The model only gives credit for  1⁄2
of these payments. 

	**	excludes  1⁄2 of the research payments of $380,000 in the total 

True up calculation: 
  

					
	 Total sublicensee payments
	  	$	27.00M	  
	 less 2 times (medx commercial fee, milestones achieved and  1⁄2 research support) ($12.38 x 2)
	  	 	($24.76M)	  
		  	  
	  
	 
		  	$	 2.24M	  
		  	 	x .175	  
		  	  
	  
	 
		  	$	.392M	  
	 plus: Medx commercial fee, milestone achieved and
 1⁄2 research support
	  	$	12.38M	  
		  	  
	  
	 
	 Amount Medx is entitled to
	  	$	12.772M	  
	 Amount paid to date**
	  	 	($12.643)	  
		  	  
	  
	 
	 Amount due to Medx
	  	$	0.129M	  

 After payment FG has received net $13.851 and Mederex has received $13.152 ($12.772 + $.380 of research
support) 
 Scenario IV 
  

							
	 Sublicensee Non-royalty
Revenue Payments
	  	 FibroGen Share

(82 1⁄2%)
	  	 Medarex Share

(17 1⁄2%)
	  	 FG-Medx Contract Research support,
Commercial License Fee or
Milestones

		  		  		  	$.760 M of quarterly pmts*
		  		  		  	$1.0M
	Phase II commencement	  		  		  	$1.0M
	Middle Phase II	  	$2.38M* ((1/2 x $.76)+$1M)	  	—	  	
	upfront fee $3M	  	$.512	  	$0.109M	  	
		  	(net total $.132M)	  	(total $2.489**)	  	

  

	*	Assume the research period spans 8 quarters at $95,000 a quarter with a total of $760,000. The model only gives credit for  1⁄2
of these payments. 

	**	excludes  1⁄2 of the research payments of $380,000 in the total 

Assume termination of during phase II which triggers true up mechanism 

True up calculation 
  

					
	 Total sublicensee payments
	  	$	3 M	  
	 less 2 times (medx commercial fee, milestones achieved and  1⁄2 research support) (2 x $2.38)
	  	 	($4.76M)	  
		  	  
	  
	 
		  	 	($1.76M)	  
		  	 	x .175	  
		  	  
	  
	 
	 the greater of zero or
	  	 	($3.08)M	  
	 plus: Medx commercial fee, milestone achieved and
 1⁄2 research support
	  	$	2.38M	  
		  	  
	  
	 
	 Amount Medx is entitled to
	  	$	2.38M	  
	 Amount paid to date**
	  	 	($2.489M)	  
		  	  
	  
	 
	 Amount due to Medx
	  	 	($0.109M)	  

 After payment back to FibroGen, FibroGen has received net $.241M ($.132 + $.109M) and Mederex has received net $2.38M

Source: [{"source": "alea-institute/alea-institute/kl3m-data-edgar-agreements/train-00236-of-00352.parquet"}, [{"source": "alea-institute/alea-institute/kl3m-data-edgar-agreements/train-00236-of-00352.parquet"}]]