TENTH AMENDMENT TO LEASE

THIS TENTH AMENDMENT TO LEASE (this “Amendment”) is entered into as of this 15th
day of September, 2020 (the “Tenth Amendment Execution Date”), by and between
BMR-201 ELLIOTT AVENUE LLC, a Delaware limited liability company (“Landlord”),
and OMEROS CORPORATION, a Washington corporation (“Tenant”).

RECITALS

A.WHEREAS, Landlord and Tenant are parties to that certain Lease dated as of
January 27, 2012 (the “Original Lease”), as amended by that certain First
Amendment to Lease dated as of November 5, 2012, that certain Second Amendment
to Lease dated as of November 16, 2012 (the “Second Amendment”), that certain
Third Amendment to Lease dated as of October 16, 2013, that certain Fourth
Amendment to Lease dated as of September 8, 2015, that certain Fifth Amendment
to Lease dated as of September 1, 2016, that certain Sixth Amendment to Lease
dated as of October 18, 2018, that certain Seventh Amendment to Lease dated as
of April 15, 2019, that certain Eighth Amendment to Lease dated as of October
28, 2019 and that certain Ninth Amendment to Lease dated as of January 15, 2020
(collectively, and as the same may have been further amended, amended and
restated, supplemented or modified from time to time, the “Existing Lease”),
whereby Tenant leases certain premises (the “Existing Premises”) from Landlord
at 201 Elliott Avenue West in Seattle, Washington (the “Building”), including
certain space within the Building’s vivarium (such portion of the Building’s
vivarium currently leased to Tenant, the “Tenant’s Existing Vivarium Space”),
which excludes the Additional Vivarium Premises comprising approximately 5,177
square feet of Rentable Area that Tenant leased from Landlord pursuant to the
Second Amendment, with respect to which Tenant exercised its right to terminate
pursuant to that certain letter dated December 17, 2015 from Tenant to Landlord;
B.WHEREAS, Tenant desires to lease additional premises from Landlord in the
Building’s vivarium; and
C.WHEREAS, Landlord and Tenant desire to modify and amend the Existing Lease
only in the respects and on the conditions hereinafter stated.

AGREEMENT

NOW, THEREFORE, Landlord and Tenant, in consideration of the mutual promises
contained herein and for other good and valuable consideration, the receipt and
sufficiency of which are hereby acknowledged, and intending to be legally bound,
agree as follows:

1.Definitions.  For purposes of this Amendment, capitalized terms shall have the
meanings ascribed to them in the Existing Lease unless otherwise defined herein.
 The Existing Lease, as amended by this Amendment, is referred to collectively
herein as the “Lease.” From and after the date hereof, the term “Lease,” as used
in the Existing Lease, shall mean the Existing Lease, as amended by this
Amendment.
2.Seventh Additional Vivarium Premises.  Effective as of the Tenth Amendment
Execution Date, Landlord hereby leases to Tenant, and Tenant hereby leases from
Landlord, approximately one thousand two hundred sixty-two (1,262) aggregate
additional square feet of

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Rentable Area located collectively in Room 141 (consisting of approximately five
hundred ninety-two (592) square feet of Rentable Area) and Room 152 (consisting
of approximately six hundred seventy (670) square feet of Rentable Area) of the
Vivarium, as shown on Exhibit A attached hereto (collectively, the “Seventh
Additional Vivarium Premises”), for use by Tenant in accordance with the
Permitted Use and in accordance with all other terms and conditions of the
Lease.  From and after the Tenth Amendment Execution Date, the term “Premises,”
as used in the Lease shall mean the Existing Premises plus the Seventh
Additional Vivarium Premises, and the term “Tenant’s Vivarium Space,” as used in
the Lease, shall mean the Tenant’s Existing Vivarium Space plus the Seventh
Additional Vivarium Premises.
3.Seventh Additional Vivarium Term.  The Term of the Lease with respect to the
Seventh Additional Vivarium Premises (as the same may be earlier terminated in
accordance with the Lease, the “Seventh Additional Vivarium Term”) shall
commence on the Tenth Amendment Execution Date and shall expire on the Term
Expiration Date.  Failure by Tenant to obtain validation by any medical review
board or other similar governmental licensing of the Seventh Additional Vivarium
Premises required for the Permitted Use by Tenant shall not serve to extend the
commencement of the Seventh Additional Vivarium Term.
4.Condition of Seventh Additional Vivarium Premises.  Tenant acknowledges that
neither Landlord nor any agent of Landlord has made any representation or
warranty with respect to the condition of the Seventh Additional Vivarium
Premises or with respect to the suitability of the Seventh Additional Vivarium
Premises for the conduct of Tenant’s business.  Tenant acknowledges that (a) it
is fully familiar with the condition of the Seventh Additional Vivarium Premises
and agrees to take the same in its condition “as is” as of the Tenth Amendment
Execution Date and (b) Landlord shall have no obligation to alter, repair or
otherwise prepare the Seventh Additional Vivarium Premises for Tenant’s
occupancy or to pay for or construct any improvements to the Seventh Additional
Vivarium Premises.  Tenant’s taking of possession of the Seventh Additional
Vivarium Premises shall, except as otherwise agreed to in writing by Landlord
and Tenant, conclusively establish that the Seventh Additional Vivarium Premises
were at such time in good, sanitary and satisfactory condition and repair.
5.Base Rent and Additional Rent.  In addition to all Base Rent for the Existing
Premises, commencing on the Tenth Amendment Execution Date and continuing for
the duration of the Seventh Additional Vivarium Term, Tenant shall pay to
Landlord (in accordance with the provisions of the Lease) Base Rent for the
Seventh Additional Vivarium Premises.  Base Rent (including the monthly
installments of Base Rent) for the Seventh Additional Vivarium Premises shall
equal the applicable amounts set forth on Exhibit B attached hereto.  In
addition to all Additional Rent for the Existing Premises, commencing as of the
Tenth Amendment Execution Date and continuing for the duration of the Seventh
Additional Vivarium Term, Tenant shall pay to Landlord Additional Rent (as
defined in (and in accordance with the provisions of) the Lease) with respect to
the Seventh Additional Vivarium Premises.
6.Pro Rata Share.  Tenant’s Pro Rata Share of the Project with respect to the
Seventh Additional Vivarium Premises shall be 0.83%.  Therefore, commencing as
of the Tenth Amendment Execution Date, Tenant’s Pro Rata Share of the Project
for the entire Premises (i.e., the Existing Premises plus the Seventh Additional
Vivarium Premises) shall be 74.44%.

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7.Termination Option.  Notwithstanding anything to the contrary in the Lease,
Tenant shall have the right to terminate the Lease, but only with respect to the
Seventh Additional Vivarium Premises (and no less than all of the Seventh
Additional Vivarium Premises), by providing written notice (the “Seventh
Additional Vivarium Termination Notice”) to Landlord at least sixty (60) days
prior to Tenant’s desired termination date (the “Seventh Additional Vivarium
Termination Date”), which Seventh Additional Vivarium Termination Date shall be
set forth in the Seventh Additional Vivarium Termination Notice.  Subject to (a)
Landlord’s timely receipt of the Seventh Additional Vivarium Termination Notice
and (b) Tenant surrendering the Seventh Additional Vivarium Premises in the
condition required under the Lease (including, without limitation, Section 18.2
and Article 26 of the Lease), then, as of the Seventh Additional Vivarium
Termination Date, the Lease with respect to the Seventh Additional Vivarium
Premises only shall terminate and be of no further force or effect, and Landlord
and Tenant shall be relieved of their respective obligations under the Lease
with respect to the Seventh Additional Vivarium Premises only from and after the
Seventh Additional Vivarium Termination Date, except with respect to those
obligations set forth in the Lease that expressly survive the expiration or
earlier termination thereof, including payment by Tenant of all amounts owed by
Tenant pursuant to the Lease with respect to the Seventh Additional Vivarium
Premises for the period up to and including the Seventh Additional Vivarium
Termination Date.  The termination right granted to Tenant pursuant to this
Section shall automatically terminate and be of no further force or effect in
the event that (y) Tenant assigns, subleases or otherwise Transfers the Seventh
Additional Vivarium Premises or any portion thereof to other entities or
persons, other than in connection with an Exempt Transfer (or in connection with
any sublease approved by Landlord pursuant to Article 29 of the Lease), or (z)
Tenant’s right to possession of the Seventh Additional Vivarium Premises has
previously been terminated.  The termination right granted to Tenant pursuant to
this Section is personal to Omeros Corporation, a Washington corporation
(“Omeros”) and any Permitted Transferees of Omeros, and may not be exercised by
any other assignee, sublessee or transferee of Tenant’s or a Permitted
Transferee’s interest in the Lease.
8.Broker. Tenant represents and warrants that it has not dealt with any broker
or agent in the negotiation for or the obtaining of this Amendment and agrees to
reimburse, indemnify, save, defend (at Landlord’s option and with counsel
reasonably acceptable to Landlord, at Tenant’s sole cost and expense) and hold
harmless the Landlord Indemnitees for, from and against any and all cost or
liability for compensation claimed by any such broker or agent employed or
engaged by it or claiming to have been employed or engaged by it.
9.No Default.  Tenant represents, warrants and covenants that, to the best of
Tenant’s knowledge, Landlord and Tenant are not in default of any of their
respective obligations under the Existing Lease and no event has occurred that,
with the passage of time or the giving of notice (or both) would constitute a
default by either Landlord or Tenant thereunder.
10.Effect of Amendment.  Except as modified by this Amendment, the Existing
Lease and all the covenants, agreements, terms, provisions and conditions
thereof shall remain in full force and effect and are hereby ratified and
affirmed.  In the event of any conflict between the terms contained in this
Amendment and the Existing Lease, the terms herein contained shall supersede and
control the obligations and liabilities of the parties.

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11.Successors and Assigns.  Each of the covenants, conditions and agreements
contained in this Amendment shall inure to the benefit of and shall apply to and
be binding upon the parties hereto and their respective heirs, legatees,
devisees, executors, administrators and permitted successors and assigns and
sublessees.  Nothing in this section shall in any way alter the provisions of
the Lease restricting assignment or subletting.
12.Miscellaneous.  This Amendment becomes effective only upon execution and
delivery hereof by Landlord and Tenant. The captions of the paragraphs and
subparagraphs in this Amendment are inserted and included solely for convenience
and shall not be considered or given any effect in construing the provisions
hereof.  All exhibits hereto are incorporated herein by reference.  Submission
of this instrument for examination or signature by Tenant does not constitute a
reservation of or option for a lease, and shall not be effective as a lease,
lease amendment or otherwise until execution by and delivery to both Landlord
and Tenant.
13.Authority.  Tenant guarantees, warrants and represents that the individual or
individuals signing this Amendment have the power, authority and legal capacity
to sign this Amendment on behalf of and to bind all entities, corporations,
partnerships, limited liability companies, joint venturers or other
organizations and entities on whose behalf such individual or individuals have
signed.
14.Counterparts; Facsimile, Electronic and PDF Signatures.  This Amendment may
be executed in one or more counterparts, each of which, when taken together,
shall constitute one and the same document.  A facsimile, electronic or portable
document format (PDF) signature on this Amendment shall be equivalent to, and
have the same force and effect as, an original signature.

[REMAINDER OF THIS PAGE INTENTIONALLY LEFT BLANK]

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IN WITNESS WHEREOF, Landlord and Tenant have executed this Amendment as of the
date and year first above written.

LANDLORD:

BMR-201 ELLIOTT AVENUE LLC,

a Delaware limited liability company

By:

/s/ Kevin M. Simonsen

Name:

Kevin M. Simonsen

Title:

EVP & General Counsel

TENANT:

OMEROS CORPORATION,

a Washington corporation

By:

/s/ Michael Jacobsen

Name:

Michael Jacobsen

Title:

VP, Finance and Chief Accounting Officer

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EXHIBIT A

SEVENTH ADDITIONAL VIVARIUM PREMISES

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EXHIBIT B

BASE RENT FOR SEVENTH ADDITIONAL VIVARIUM PREMISES

Dates

Square Feet of Rentable Area

Annual Base Rent per Square Foot Of Rentable Area

Monthly Base Rent

Tenth Amendment
Execution Date -
November 15, 2020

1,262

$73.79

$7,760.25

November 16, 2020-
November 15, 2021

1,262

$76.01

$7,993.72

November 16, 2021-
November 15, 2022

1,262

$78.29

$8,233.50

November 16, 2022-
November 15, 2023

1,262

$80.63

$8,479.59

November 16, 2023-
November 15, 2024

1,262

$83.05

$8,734.09

November 16, 2024-
November 15, 2025

1,262

$85.55

$8,997.01

November 16, 2025-
November 15, 2026

1,262

$88.11

$9,266.24

November 16, 2026-
November 15, 2027

1,262

$90.76

$9,544.93

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