Exhibit 10.3


 


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REGISTRATION RIGHTS AGREEMENT


 


This Registration Rights
Agreement (this “Agreement”) is dated as of October 31, 2017, by and among Soligenix, Inc., a Delaware corporation
(the “Company”), and the Investors signatory hereto (each such Investor, an “Investor” and
collectively, the “Investors”).


 


WHEREAS, this
Agreement is made pursuant to the Securities Purchase Agreement dated as of the date hereof among the Company and the Investors
(the “Purchase Agreement”).


 


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in consideration of the mutual covenants contained in this Agreement, and for other good and valuable consideration the receipt
and adequacy of which are hereby acknowledged, the Company and the Investors agree as follows:


 


1. Definitions.  Capitalized
terms used and not otherwise defined herein that are defined in the Purchase Agreement shall have the meanings given such terms
in the Purchase Agreement.  As used in this Agreement, the following terms shall have the following meanings:


 


“Advice”
shall have the meaning set forth in Section 6(c).


 


“Common Stock”
means the common stock of the Company, par value $0.001 per share, and any securities into which such common stock may hereafter
be classified.


 


“Effectiveness
Date” means, (a) with respect to the initial Registration Statement required to be filed hereunder, the earlier of (i)
the 90th calendar day following the Closing Date, and (ii) the fifth Trading Day following the date on which the Company is notified
by the Commission that the Registration Statement will not be reviewed or is no longer subject to further review and comments,
and (b) with respect to any additional Registration Statement(s) that may be required pursuant to Section 2(b), the earlier of
(i) the 120th calendar day following (x) the date or time on which the Commission shall indicate as being the first date or time
that such Registrable Securities may then be included in a Registration Statement, if such Registration Statement is required because
the Commission shall have notified the Company in writing that certain Registrable Securities were not eligible for inclusion on
a previously filed Registration Statement,  or (y) the date on which the Company first knows, or reasonably should have
known, that such additional Registration Statement(s) is required if such Registration Statement is required for a reason other
than as described in (x) above, and (ii) the fifth Trading Day following the date on which the Company is notified by the Commission
that such additional Registration Statement will not be reviewed or is no longer subject to further review and comments.


 


“Effectiveness
Period” shall have the meaning set forth in Section 2(a).


 


“Event”
shall have the meaning set forth in Section 2(c).


 


“Event Date”
shall have the meaning set forth in Section 2(c).


 






     


     


    

 


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“Filing Date”
means, with (a) respect to the initial Registration Statement required to be filed hereunder, the 30th Day after the Closing, and
(b) with respect to any additional Registration Statements that may be required pursuant to Section 2(b), the 20th day following
(x) the date or time on which the Commission shall indicate as being the first date or time that such Registrable Securities may
then be included in a Registration Statement, if such Registration Statement is required because the Commission shall have notified
the Company in writing that certain Registrable Securities were not eligible for inclusion on a previously filed Registration Statement,  or
(y) the date on which the Company first knows, or reasonably should have known, that such additional Registration Statements is
required if such Registration Statement is required for a reason other than as described in (x) above.


 


“Force Majeure”
shall mean any unusual event arising from causes reasonably beyond the control of the Company that could not be reasonably anticipated
that causes a delay in or prevents the performance of any obligation under this Agreement, including but not limited to, acts of
God, fire, war, terrorism, insurrection, civil disturbance, explosion, adverse weather conditions, unusual delay in transportation,
strikes or other labor disputes, and restraint by court order or order of public authority.


 


“Grace Period”
shall have the meaning set forth in Section 2(c)(iv).


 


“Holder”
or “Holders” means the holder or holders, as the case may be, from time to time of Registrable Securities.


 


“Indemnified
Party” shall have the meaning set forth in Section 5(c).


 


“Indemnifying
Party” shall have the meaning set forth in Section 5(c).


 


“Losses”
shall have the meaning set forth in Section 5(a).


 


“Proceeding”
means an action, claim, suit, investigation or proceeding (including, without limitation, an investigation or partial proceeding,
such as a deposition), whether commenced or threatened.


 


“Prospectus”
means the prospectus included in a Registration Statement (including, without limitation, a prospectus that includes any information
previously omitted from a prospectus filed as part of an effective registration statement in reliance upon Rule 430A promulgated
under the Securities Act), as amended or supplemented by any prospectus supplement, with respect to the terms of the offering of
any portion of the Registrable Securities covered by the Registration Statement, and all other amendments and supplements to the
Prospectus, including post-effective amendments, and all material incorporated by reference or deemed to be incorporated by reference
in such Prospectus.


 


“Registrable
Securities” means all of the Shares, together with any shares of Common Stock issued or issuable upon any stock split,
dividend or other distribution, recapitalization or similar event with respect to the foregoing.


 


“Registration
Statement” means the registration statement(s) required to be filed hereunder, including (in each case) the Prospectus,
amendments and supplements to such registration statement(s) or Prospectus, including pre- and post-effective amendments, all exhibits
thereto, and all material incorporated by reference or deemed to be incorporated by reference in such registration statement(s).


 






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“Response Date”
shall have the meaning set forth in Section 2(c)(ii).


 


“Rule 415”
means Rule 415 promulgated by the Commission pursuant to the Securities Act, as such Rule may be amended from time to time, or
any similar rule or regulation hereafter adopted by the Commission having substantially the same purpose and effect as such Rule.


 


“Rule 424”
means Rule 424 promulgated by the Commission pursuant to the Securities Act, as such Rule may be amended from time to time, or
any similar rule or regulation hereafter adopted by the Commission having substantially the same purpose and effect as such Rule.


 


2. Registration.


 


(a) On or prior
to each Filing Date, the Company shall prepare and file with the Commission the Registration Statement covering the resale of all
of the Registrable Securities for an offering to be made on a continuous basis pursuant to Rule 415.  The Registration
Statement required hereunder shall be on Form S-1 (except if the Company is not then eligible to register for resale the Registrable
Securities on Form S-1, in which case the Registration shall be on another appropriate form in accordance herewith).  The
Registration Statement required hereunder shall contain (except if otherwise directed by the Holders) the “Plan of Distribution”
attached hereto as Annex A.  Subject to the terms of this Agreement, the Company shall use its best efforts to
cause the Registration Statement to be declared effective under the Securities Act as promptly as possible after the filing thereof,
but in any event not later than the Effectiveness Date, and shall use its best efforts to keep the Registration Statement continuously
effective under the Securities Act until the date when all Registrable Securities covered by the Registration Statement have been
sold or may be sold without volume restrictions pursuant to Rule 144(b)(1) as determined by the counsel to the Company pursuant
to a written opinion letter to such effect, addressed and acceptable to the Company’s transfer agent and the affected Holders
(the “Effectiveness Period”).


 


(b) If for any
reason the Commission does not permit all of the Shares to be included in the Registration Statement filed pursuant to Section
2(a), then the Registrable Securities that are included in such offering shall be allocated among the Holders in proportion (as
nearly as practicable) to the number of Registrable Securities owned by each Holder, or in such other proportions as shall mutually
be agreed to by all such Holders.  To facilitate the allocation of shares in accordance with the above provisions, the
Company may round the number of shares allocated to any Holder to the nearest 100 shares.  If for any reason the Commission
does not permit all of the Shares to be included in the Registration Statement filed pursuant to Section 2(a) or for any other
reason any Registrable Securities are not then included in a Registration Statement filed under this Agreement, then the Company
shall prepare and file as soon as possible after the date on which the Commission shall indicate as being the first date or time
that such filing may be made, but in any event by its Filing Date, an additional Registration Statement covering the resale of
all Registrable Securities not already covered by an existing and effective Registration Statement for an offering to be made on
a continuous basis pursuant to Rule 415.  Each such Registration Statement shall contain (except if otherwise directed
by the Holders) the "Plan of Distribution" attached hereto as Annex A.  The Company shall use its best
efforts to cause each such Registration Statement to be declared effective under the Securities Act as soon as possible but, in
any event, no later than its Effectiveness Date, and shall use its best efforts to keep such Registration Statement continuously
effective under the Securities Act during its entire Effectiveness Period.


 






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(c) If: (i) a Registration
Statement is not filed on or prior to its Filing Date (if the Company files a Registration Statement without affording the Holders
the opportunity to review and comment on the same as required by Section 3(a) hereof, the Company shall not be deemed to have satisfied
this clause (i)), or (ii) prior to the date when such Registration Statement is first declared effective by the Commission, the
Company fails to file a pre-effective amendment and otherwise respond in writing to comments made by the Commission in respect
of such Registration Statement within 20 calendar days (the “Response Date”) after the receipt of comments by
or notice from the Commission that such amendment is required in order for such Registration Statement to be declared effective,
or (iii) a Registration Statement filed or required to be filed hereunder is not declared effective by the Commission on or before
its Effectiveness Date, or (iv) during the Effectiveness Period, a Registration Statement ceases for any reason to remain continuously
effective as to all Registrable Securities for which it is required to be effective, or the Holders are not permitted to utilize
the Prospectus therein to resell such Registrable Securities, for in any and all such cases for more than an aggregate of 5 Trading
Days (the “Grace Period”) during any 12-month period during the Effectiveness Period (which need not be consecutive
Trading Days)(any such failure or breach being referred to as an “Event,” and for purposes of clause (i) or
(iii) the date on which such Event occurs, or for purposes of clause (ii) the date which such 20 calendar days is exceeded, or
for purposes of clause (iv) the date on which such 10 Trading Days is exceeded being referred to as “Event Date”),
then in addition to any other rights the Holders may have hereunder or under applicable law: (x) on each such Event Date the Company
shall pay to each Holder an amount in cash, as partial liquidated damages and not as a penalty, equal to 1.5% of the aggregate
Investment Amount paid by such Holder pursuant to the Purchase Agreement; and (y) on each monthly anniversary of each such Event
Date (if the applicable Event shall not have been cured by such date) until the applicable Event is cured, the Company shall pay
to each Holder an amount in cash, as partial liquidated damages and not as a penalty, equal to 1.5% of the aggregate Investment
Amount paid by such Holder pursuant to the Purchase Agreement.  If the Company fails to pay any partial liquidated damages
pursuant to this Section in full within seven days after the date payable, the Company will pay interest thereon at a rate of 10%
per annum (or such lesser maximum amount that is permitted to be paid by applicable law) to the Holder, accruing daily from the
date such partial liquidated damages are due until such amounts, plus all such interest thereon, are paid in full.  The
partial liquidated damages pursuant to the terms hereof shall apply on a daily pro-rata basis for any portion of a month prior
to the cure of an Event, except in the case of the first Event Date.  Notwithstanding the foregoing, any day on which
a Force Majeure has occurred or is continuing shall not count toward the calculation of the number of days for the Filing Date,
the Effectiveness Date, the Response Date and a Grace Period.


 




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3. Registration
Procedures


 


In connection with the
Company’s registration obligations hereunder, the Company shall:


 


(a) Not less than
five Trading Days prior to the filing of a Registration Statement or any related Prospectus or any amendment or supplement thereto,
the Company shall furnish to the Holders copies of the “Selling Stockholders” and the “Plan of Distribution”
sections and any risk factor contained in such document that addresses specifically this transaction or the Selling Stockholders,
as proposed to be filed which documents will be subject to the review of such Holders.


 


(b)  (i) Prepare
and file with the Commission such amendments, including post-effective amendments, to the Registration Statement and the Prospectus
used in connection therewith as may be necessary to keep the Registration Statement continuously effective as to the applicable
Registrable Securities for the Effectiveness Period and prepare and file with the Commission such additional Registration Statements
in order to register for resale under the Securities Act all of the Registrable Securities; (ii) cause the related Prospectus to
be amended or supplemented by any required Prospectus supplement, and as so supplemented or amended to be filed pursuant to Rule
424; (iii) respond as promptly as reasonably possible to any comments received from the Commission with respect to the Registration
Statement or any amendment thereto and, as promptly as reasonably possible, upon request, provide the Holders true and complete
copies of all correspondence from and to the Commission relating to the Registration Statement; and (iv) comply in all material
respects with the provisions of the Securities Act and the Exchange Act with respect to the disposition of all Registrable Securities
covered by the Registration Statement (to the extent such provisions are applicable to the Company).  Notwithstanding
anything else contained herein to the contrary, the Company shall not provide any material, nonpublic information to the Holders.


 


(c) Notify the
Holders of Registrable Securities as promptly as reasonably possible (and, in the case of (i)(A) below, not less than two Trading
Days prior to such filing) and (if requested by any such Person) confirm such notice in writing promptly following the day (i)(A)
when a Prospectus or any Prospectus supplement or post-effective amendment to the Registration Statement is proposed to be filed;
(B) when the Commission notifies the Company whether there will be a “review” of the Registration Statement and whenever
the Commission comments in writing on the Registration Statement (the Company shall provide copies thereof and all written responses
thereto to each of the Holders to the extent such materials address the Selling Stockholder or Plan of Distribution sections of
such Registration Statement, and to the extent they address risk factors or other disclosure in such Registration Statement particular
to the Holder or the transactions contemplated hereby); and (C) with respect to the Registration Statement or any post-effective
amendment, when the same has become effective; (ii) of any request by the Commission or any other Federal or state governmental
authority during the period of effectiveness of the Registration Statement for amendments or supplements to the Registration Statement
or Prospectus or for additional information; (iii) of the issuance by the Commission or any other federal or state governmental
authority of any stop order suspending the effectiveness of the Registration Statement covering any or all of the Registrable Securities
or the initiation of any Proceedings for that purpose; (iv) of the receipt by the Company of any notification with respect to the
suspension of the qualification or exemption from qualification of any of the Registrable Securities for sale in any jurisdiction,
or the initiation or threatening of any Proceeding for such purpose; and (v) of the occurrence of any event or passage of time
that makes the financial statements included in the Registration Statement ineligible for inclusion therein or any statement made
in the Registration Statement or Prospectus or any document incorporated or deemed to be incorporated therein by reference untrue
in any material respect or that requires any revisions to the Registration Statement, Prospectus or other documents so that, in
the case of the Registration Statement or the Prospectus, as the case may be, it will not contain any untrue statement of a material
fact or omit to state any material fact required to be stated therein or necessary to make the statements therein, in light of
the circumstances under which they were made, not misleading.


 






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(d) Use reasonable
best efforts to avoid the issuance of, or, if issued, obtain the withdrawal of (i) any order suspending the effectiveness of the
Registration Statement, or (ii) any suspension of the qualification (or exemption from qualification) of any of the Registrable
Securities for sale in any jurisdiction, at the earliest practicable moment.


 


(e) Deliver to
each Holder, by 12:00 p.m. (New York City time) on the date following the Effective Date, without charge, as many copies of the
Prospectus or Prospectuses (including each form of prospectus) and each amendment or supplement thereto as such Persons may reasonably
request in connection with resales by the Holder of Registrable Securities.  Subject to the terms of this Agreement,
the Company hereby consents to the use of such Prospectus and each amendment or supplement thereto by each of the selling Holders
in connection with the offering and sale of the Registrable Securities covered by such Prospectus and any amendment or supplement
thereto, subject to notices pursuant to Section 3(c).


 


(f) Prior to any
resale of Registrable Securities by a Holder, use its commercially reasonable efforts to register or qualify or cooperate with
the selling Holders in connection with the registration or qualification (or exemption from the Registration or qualification)
of such Registrable Securities for the resale by the Holder under the securities or Blue Sky laws of such jurisdictions within
the United States as any Holder reasonably requests in writing, to keep the Registration or qualification (or exemption therefrom)
effective during the Effectiveness Period and to do any and all other acts or things reasonably necessary to enable the disposition
in such jurisdictions of the Registrable Securities covered by the Registration Statement; provided, that the Company shall
not be required to qualify generally to do business or file a general consent to service of process in any jurisdiction where it
is not then so qualified.


 


(g) If requested
by the Holders, cooperate with each Holder to facilitate the timely preparation and delivery of certificates representing Registrable
Securities to be delivered to a transferee pursuant to the Registration Statement, which certificates shall be free, to the extent
permitted by the Purchase Agreement, of all restrictive legends, and to enable such Registrable Securities to be in such denominations
and registered in such names as any such Holders may request.


 






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(h) Upon the occurrence
of any event contemplated by this Section 3, as promptly as commercially reasonably possible under the circumstances taking into
account the Company’s good faith assessment of any adverse consequences to the Company and its stockholders of the premature
disclosure of such events, prepare a supplement or amendment, including a post-effective amendment, to the Registration Statement
or a supplement to the related Prospectus or any document incorporated or deemed to be incorporated therein by reference, and file
any other required document so that, as thereafter delivered, neither the Registration Statement nor such Prospectus will contain
an untrue statement of a material fact or omit to state a material fact required to be stated therein or necessary to make the
statements therein, in light of the circumstances under which they were made, not misleading. If the Company notifies the
Holders in accordance with clauses (ii) through (v) of Section 3(c) above to suspend the use of any Prospectus until the requisite
changes to such Prospectus have been made, then the Holders shall suspend use of such Prospectus.  The Company will use
its best efforts to ensure that the use of the Prospectus may be resumed as promptly as is commercially practicable.  The
Company shall be entitled to exercise its right under this Section 3(h) to suspend the availability of a Registration Statement
and Prospectus, subject to the payment of liquidated damages pursuant to Section 2(c), for a period not to exceed 60 days (which
need not be consecutive days) in any 12 month period.


 


(i) Comply with
all applicable rules and regulations of the Commission.


 


(j) Each Holder
agrees to furnish to the Company a completed Questionnaire in the form attached to this Agreement as Annex B (a “Selling
Holder Questionnaire”).  The Company shall not be required to include the Registrable Securities of a Holder
in a Registration Statement and shall not be required to pay any liquidated or other damages under Section 2(c) to such Holder
who fails to furnish to the Company a fully completed Selling Holder Questionnaire at least one Trading Day prior to the Filing
Date (subject to the requirements set forth in Section 3(a)).


 


(k)  Upon
notification by the Commission that a Registration Statement will not be reviewed or is no longer subject to further review and
comments, the Company shall request acceleration of such Registration Statement such that it becomes effective at 4:00 p.m. (New
York City time) on the Effective Date.


 


4. Registration
Expenses.  All fees and expenses incident to the performance of or compliance with this Agreement by the Company
shall be borne by the Company whether or not any Registrable Securities are sold pursuant to the Registration Statement.  The
fees and expenses referred to in the foregoing sentence shall include, without limitation, (i) all registration and filing fees
(including, without limitation, fees and expenses (A) with respect to filings required to be made with the Principal Market on
which the Common Stock is then listed for trading, and (B) in compliance with applicable state securities or Blue Sky laws), (ii)
printing expenses (including, without limitation, expenses of printing certificates for Registrable Securities and of printing
prospectuses if the printing of prospectuses is reasonably requested by the holders of a majority of the Registrable Securities
included in the Registration Statement), (iii) messenger, telephone and delivery expenses, (iv) fees and disbursements of counsel
for the Company, (v) Securities Act liability insurance, if the Company so desires such insurance, and (vi) fees and expenses of
all other Persons retained by the Company in connection with the consummation of the transactions contemplated by this Agreement.  In
addition, the Company shall be responsible for all of its internal expenses incurred in connection with the consummation of the
transactions contemplated by this Agreement (including, without limitation, all salaries and expenses of its officers and employees
performing legal or accounting duties), the expense of any annual audit and the fees and expenses incurred in connection with the
listing of the Registrable Securities on any securities exchange or market as required hereunder. In no event shall the Company
be responsible for any broker or similar commissions of the Holders.


 






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5. Indemnification


 


(a) Indemnification
by the Company.  The Company shall, notwithstanding any termination of this Agreement, indemnify and hold harmless
each Holder, the officers, directors, agents and employees of each of them, each Person who controls any such Holder (within the
meaning of Section 15 of the Securities Act or Section 20 of the Exchange Act) and the officers, directors, agents and employees
of each such controlling Person, to the fullest extent permitted by applicable law, from and against any and all losses, claims,
damages, liabilities, costs (including, without limitation, reasonable attorneys' fees) and expenses (collectively, “Losses”),
as incurred, arising out of or relating to any untrue or alleged untrue statement of a material fact contained in the Registration
Statement, any Prospectus or any form of prospectus or in any amendment or supplement thereto or in any preliminary prospectus,
or arising out of or relating to any omission or alleged omission of a material fact required to be stated therein or necessary
to make the statements therein (in the case of any Prospectus or form of prospectus or supplement thereto, in light of the circumstances
under which they were made) not misleading, except to the extent, but only to the extent, that (i) such untrue statements or omissions
are based solely upon information regarding such Holder furnished in writing to the Company by such Holder expressly for use therein,
or to the extent that such information relates to such Holder or such Holder's proposed method of distribution of Registrable Securities
and was reviewed and expressly approved in writing by such Holder expressly for use in the Registration Statement, such Prospectus
or such form of Prospectus or in any amendment or supplement thereto (it being understood that the Holder has approved Annex A
hereto for this purpose), (ii) in the case of an occurrence of an event of the type specified in Section 3(c)(ii)-(v), the use
by such Holder of an outdated or defective Prospectus after the Company has notified such Holder in writing that the Prospectus
is outdated or defective and prior to the receipt by such Holder of the Advice or an amended or supplemented Prospectus, but only
if and to the extent that following the receipt of the Advice or the amended or supplemented Prospectus the misstatement or omission
giving rise to such Loss would have been corrected or (iii) such Holder fails to comply with any applicable prospectus delivery
requirements of the Securities Act applicable to it in connection with sales of Registrable Securities pursuant to a Registration
Statement.  The Company shall notify the Holders promptly of the institution, threat or assertion of any Proceeding of
which the Company is aware in connection with the transactions contemplated by this Agreement.


 


(b) Indemnification
by Holders. Each Holder shall, severally and not jointly, indemnify and hold harmless the Company, its directors, officers,
agents and employees, each Person who controls the Company (within the meaning of Section 15 of the Securities Act and Section
20 of the Exchange Act), and the directors, officers, agents or employees of such controlling Persons, to the fullest extent permitted
by applicable law, from and against all Losses, as incurred, arising solely out of or based solely upon: (x) such Holder's failure
to comply with the prospectus delivery requirements of the Securities Act to the extent that delivery of such Prospectus would
have avoided such Loss or (y) any untrue or alleged untrue statement of a material fact contained in any Registration Statement,
any Prospectus, or any form of prospectus, or in any amendment or supplement thereto or in any preliminary prospectus, or arising
solely out of or based solely upon any omission or alleged omission of a material fact required to be stated therein or necessary
to make the statements therein not misleading to the extent, but only to the extent, that such untrue statements or omissions are
based solely upon information regarding such Holder furnished in writing to the Company by such Holder expressly for use therein.
In no event shall the liability of any selling Holder hereunder be greater in amount than the dollar amount of the net proceeds
received by such Holder upon the sale of the Registrable Securities giving rise to such indemnification obligation.


 






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(c) Conduct
of Indemnification Proceedings. If any Proceeding shall be brought or asserted against any Person entitled to indemnity hereunder
(an “Indemnified Party”), such Indemnified Party shall promptly notify the Person from whom indemnity is sought
(the “Indemnifying Party”) in writing, and the Indemnifying Party shall have the right to assume the defense
thereof, including the employment of counsel reasonably satisfactory to the Indemnified Party and the payment of all fees and expenses
incurred in connection with defense thereof; provided, that the failure of any Indemnified Party to give such notice shall not
relieve the Indemnifying Party of its obligations or liabilities pursuant to this Agreement, except (and only) to the extent that
it shall be finally determined by a court of competent jurisdiction (which determination is not subject to appeal or further review)
that such failure shall have proximately and materially prejudiced the Indemnifying Party.


 


An Indemnified Party
shall have the right to employ separate counsel in any such Proceeding and to participate in the defense thereof, but the fees
and expenses of such counsel shall be at the expense of such Indemnified Party or Parties unless:  (1) the Indemnifying
Party has agreed in writing to pay such fees and expenses; (2) the Indemnifying Party shall have failed promptly to assume the
defense of such Proceeding and to employ counsel reasonably satisfactory to such Indemnified Party in any such Proceeding; or (3)
the named parties to any such Proceeding (including any impleaded parties) include both such Indemnified Party and the Indemnifying
Party, and such Indemnified Party shall have been advised by counsel that a material conflict of interest is likely to exist if
the same counsel were to represent such Indemnified Party and the Indemnifying Party (in which case, if such Indemnified Party
notifies the Indemnifying Party in writing that it elects to employ separate counsel at the expense of the Indemnifying Party,
the Indemnifying Party shall not have the right to assume the defense thereof and the reasonable fees and expenses of up to an
aggregate of three separate counsel shall be at the expense of the Indemnifying Party).  The Indemnifying Party shall
not be liable for any settlement of any such Proceeding effected without its written consent.  No Indemnifying Party
shall, without the prior written consent of the Indemnified Party, effect any settlement of any pending Proceeding in respect of
which any Indemnified Party is a party, unless such settlement includes an unconditional release of such Indemnified Party from
all liability on claims that are the subject matter of such Proceeding.


 


Subject to the terms
of this Agreement, all reasonable fees and expenses of the Indemnified Party (including reasonable fees and expenses to the extent
incurred in connection with investigating or preparing to defend such Proceeding in a manner not inconsistent with this Section)
shall be paid to the Indemnified Party, as incurred, within ten Trading Days of written notice thereof to the Indemnifying Party;
provided, that the Indemnified Party shall promptly reimburse the Indemnifying Party for that portion of such fees and expenses
applicable to such actions for which such Indemnified Party is not entitled to indemnification hereunder, determined based upon
the relative faults of the parties.


 






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(d) Contribution.  If
a claim for indemnification under Section 5(a) or 5(b) is unavailable to an Indemnified Party (by reason of public policy or otherwise),
then each Indemnifying Party, in lieu of indemnifying such Indemnified Party, shall contribute to the amount paid or payable by
such Indemnified Party as a result of such Losses, in such proportion as is appropriate to reflect the relative fault of the Indemnifying
Party and Indemnified Party in connection with the actions, statements or omissions that resulted in such Losses as well as any
other relevant equitable considerations.  The relative fault of such Indemnifying Party and Indemnified Party shall be
determined by reference to, among other things, whether any action in question, including any untrue or alleged untrue statement
of a material fact or omission or alleged omission of a material fact, has been taken or made by, or relates to information supplied
by, such Indemnifying Party or Indemnified Party, and the parties' relative intent, knowledge, access to information and opportunity
to correct or prevent such action, statement or omission.  The amount paid or payable by a party as a result of any Losses
shall be deemed to include, subject to the limitations set forth in this Section 5, any reasonable attorneys’ or other reasonable
fees or expenses incurred by such party in connection with any Proceeding to the extent such party would have been indemnified
for such fees or expenses if the indemnification provided for in this Section was available to such party in accordance with its
terms.


 


The parties hereto agree
that it would not be just and equitable if contribution pursuant to this Section 5(d) were determined by pro rata allocation or
by any other method of allocation that does not take into account the equitable considerations referred to in the immediately preceding
paragraph.  Notwithstanding the provisions of this Section 5(d), no Holder shall be required to contribute, in the aggregate,
any amount in excess of the amount by which the proceeds actually received by such Holder from the sale of the Registrable Securities
subject to the Proceeding exceeds the amount of any damages that such Holder has otherwise been required to pay by reason of such
untrue or alleged untrue statement or omission or alleged omission or other act in question.  No party guilty of fraudulent
misrepresentation (within the meaning of Section 11(f) of the Securities Act) shall be entitled to contribution from any party
that was not guilty of such fraudulent misrepresentation.


 


The indemnity and contribution
agreements contained in this Section are in addition to any liability that the Indemnifying Parties may have to the Indemnified
Parties.


 


6. Miscellaneous


 


(a) Remedies.  In
the event of a breach by the Company or by a Holder, of any of their obligations under this Agreement, each Holder or the Company,
as the case may be, in addition to being entitled to exercise all rights granted by law and under this Agreement, including recovery
of damages, will be entitled to specific performance of its rights under this Agreement.  The Company and each Holder
agree that monetary damages would not provide adequate compensation for any losses incurred by reason of a breach by it of any
of the provisions of this Agreement and hereby further agrees that, in the event of any action for specific performance in respect
of such breach, it shall waive the defense that a remedy at law would be adequate.


 






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(b) Compliance.  Each
Holder covenants and agrees that it will comply with the prospectus delivery requirements of the Securities Act as applicable to
it in connection with sales of Registrable Securities pursuant to the Registration Statement.


 


(c) Discontinued
Disposition.  Each Holder agrees by its acquisition of such Registrable Securities that, upon receipt of a notice
from the Company of the occurrence of any event of the kind described in Section 3(c), such Holder will forthwith discontinue disposition
of such Registrable Securities under the Registration Statement until such Holder's receipt of the copies of the supplemented Prospectus
and/or amended Registration Statement or until it is advised in writing (the “Advice”) by the Company that the
use of the applicable Prospectus may be resumed, and, in either case, has received copies of any additional or supplemental filings
that are incorporated or deemed to be incorporated by reference in such Prospectus or Registration Statement.  The Company
will use its best efforts to ensure that the use of the Prospectus may be resumed as promptly as is commercially practicable.  The
Company agrees and acknowledges that any periods during which the Holder is required to discontinue the disposition of the Registrable
Securities hereunder shall be subject to the provisions of Section 2(c).


 


(d) Piggy-Back
Registrations.  If at any time during the Effectiveness Period there is not an effective Registration Statement covering
all of the Registrable Securities and the Company shall determine to prepare and file with the Commission a registration statement
relating to an offering for its own account or the account of others under the Securities Act of any of its equity securities,
other than on Form S-4 or Form S-8 (each as promulgated under the Securities Act) or their then equivalents relating to equity
securities to be issued solely in connection with any acquisition of any entity or business or equity securities issuable in connection
with the stock option or other employee benefit plans, then the Company shall send to each Holder a written notice of such determination
and, if within fifteen days after the date of such notice, any such Holder shall so request in writing, the Company shall include
in such registration statement all or any part of such Registrable Securities such Holder requests to be registered, subject to
customary underwriter cutbacks applicable to all holders of registration rights.


 


(e) Amendments
and Waivers. Any term of this Agreement may be amended and the observance of any term of this Agreement may be waived (either
generally or in a particular instance, and either retroactively or prospectively) only with the written consent of the Company
and the Investors holding of a majority of the Shares; provided that any provision hereof may be waived by any waiving party on
such party’s own behalf, without the consent of any other party. Notwithstanding the foregoing, this Agreement may not be
amended or terminated and the observance of any term hereof may not be waived with respect to any Investor without the written
consent of such Investor, unless such amendment, termination, or waiver applies to all Investors in the same fashion. The Company
shall give prompt notice of any amendment or termination hereof or waiver hereunder to any party hereto that did not consent in
writing to such amendment, termination, or waiver. Any amendment, termination, or waiver effected in accordance with this Section
6(e) shall be binding on all parties hereto, regardless of whether any such party has consented thereto. No waiver of any default
with respect to any provision, condition or requirement of this Agreement shall be deemed to be a continuing waiver in the future
or a waiver of any subsequent default or a waiver of any other provision, condition or requirement hereof, nor shall any delay
or omission of either party to exercise any right hereunder in any manner impair the exercise of any such right.


 






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EXECUTION COPY


 


(f) Notices.  Any
and all notices or other communications or deliveries required or permitted to be provided hereunder shall be made in accordance
with the provisions of the Purchase Agreement.


 


(g) Successors
and Assigns.  This Agreement shall inure to the benefit of and be binding upon the successors and permitted assigns
of each of the parties and shall inure to the benefit of each Holder.  Each Holder may assign their respective rights
hereunder in the manner and to the Persons as permitted under the Purchase Agreement.  The Company may not assign its
rights or obligations hereunder.


 


(h) Execution
and Counterparts.  This Agreement may be executed in any number of counterparts, each of which when so executed shall
be deemed to be an original and, all of which taken together shall constitute one and the same Agreement.  In the event
that any signature is delivered by facsimile or electronic mail transmission, such signature shall create a valid binding obligation
of the party executing (or on whose behalf such signature is executed) the same with the same force and effect as if such facsimile
signature were the original thereof.


 


(i) Governing
Law.  All questions concerning the construction, validity, enforcement and interpretation of this Agreement shall
be determined with the provisions of the Purchase Agreement.


 


(j) Cumulative
Remedies.  The remedies provided herein are cumulative and not exclusive of any remedies provided by law.


 


(k) Severability.
If any term, provision, covenant or restriction of this Agreement is held by a court of competent jurisdiction to be invalid, illegal,
void or unenforceable, the remainder of the terms, provisions, covenants and restrictions set forth herein shall remain in full
force and effect and shall in no way be affected, impaired or invalidated, and the parties hereto shall use their reasonable best
efforts to find and employ an alternative means to achieve the same or substantially the same result as that contemplated by such
term, provision, covenant or restriction.  It is hereby stipulated and declared to be the intention of the parties that
they would have executed the remaining terms, provisions, covenants and restrictions without including any of such that may be
hereafter declared invalid, illegal, void or unenforceable.


 


(l) Headings.  The
headings in this Agreement are for convenience of reference only and shall not limit or otherwise affect the meaning hereof.


 


(m) Independent
Nature of Holders’ Obligations and Rights.  The obligations of each Holder hereunder are several and not joint
with the obligations of any other Holder hereunder, and no Holder shall be responsible in any way for the performance of the obligations
of any other Holder hereunder.  Nothing contained herein or in any other agreement or document delivered at any closing,
and no action taken by any Holder pursuant hereto or thereto, shall be deemed to constitute the Holders as a partnership, an association,
a joint venture or any other kind of entity, or create a presumption that the Holders are in any way acting in concert with respect
to such obligations or the transactions contemplated by this Agreement.  Each Holder acknowledges that no other Holder
has acted as agent for such Holder in connection with executing this Agreement and that no Holder will be acting as agent of such
Holder in connection with monitoring the registration of the Registrable Securities or enforcing its rights under this Agreement.  Each
Holder shall be entitled to protect and enforce its rights, including without limitation the rights arising out of this Agreement,
and it shall not be necessary for any other Holder to be joined as an additional party in any Proceeding for such purpose.  The
Company acknowledges that each of the Investors has been provided with the same Transaction Documents and will likely have their
respective Registrable Securities included on the same Registration Statement, for the purpose of closing a transaction with multiple
Investors and not because it was required or requested to do so by any Investor.


 


*************************


 




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EXECUTION COPY


 


IN WITNESS WHEREOF,
the parties have executed this Registration Rights Agreement as of the date first written above.


 


	 	SOLIGENIX, INC.
	 	 	 
	 	

By:
	    
	 	Name:	Christopher J. Schaber, Ph.D.
	 	Title:	President & CEO


 


[SIGNATURE PAGE OF HOLDERS FOLLOWS]


 




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EXECUTION COPY


 


[INVESTOR SIGNATURE PAGE TO SOLIGENIX, INC.


Registration
Rights Agreement]


 


Name of Investor: _______________________________


 


Signature: _____________________________________


 


Name of Authorized Signatory, if an entity: __________________________________


 


Title of Authorized Signatory, if an entity: ___________________________________


 


[SIGNATURE PAGES CONTINUE]


 




    	 	14	 



     


    

 


ANNEX A


 


Plan of Distribution


 


The selling stockholders
and any of their pledgees, donees, transferees, assignees and successors-in-interest may, from time to time, sell any or all of
their shares of common stock on any stock exchange, market or trading facility on which the shares are traded or in private transactions.  These
sales may be at fixed or negotiated prices.  The selling stockholders may use any one or more of the following methods
when selling shares:


 


		·	ordinary brokerage transactions and transactions in which the broker-dealer solicits investors;



 


		·	block trades in which the broker-dealer will attempt to sell the shares as agent but may position
and resell a portion of the block as principal to facilitate the transaction;



 


		·	purchases by a broker-dealer as principal and resale by the broker-dealer for its account;



 


		·	an exchange distribution in accordance with the rules of the applicable exchange;



 


		·	privately negotiated transactions;



 


		·	to cover short sales and other hedging transactions made after the date that the registration statement
of which this prospectus is a part is declared effective by the Securities and Exchange Commission;



 


		·	broker-dealers may agree with the selling stockholders to sell a specified number of such shares
at a stipulated price per share;



 


		·	a combination of any such methods of sale; and



 


		·	any other method permitted pursuant to applicable law.



 


The selling stockholders
may also sell shares under Rule 144 under the Securities Act, if available, rather than under this prospectus.


 


Broker-dealers engaged
by the selling stockholders may arrange for other brokers-dealers to participate in sales. Broker-dealers may receive
commissions or discounts from the selling stockholders (or, if any broker-dealer acts as agent for the investor of shares, from
the purchaser) in amounts to be negotiated.  The selling stockholders do not expect these commissions and discounts to
exceed what is customary in the types of transactions involved.


 






     


     


    

 


The selling stockholders
may from time to time pledge or grant a security interest in some or all of the Shares owned by them and, if they default in the
performance of their secured obligations, the pledgees or secured parties may offer and sell shares of common stock from time to
time under this prospectus, or under an amendment to this prospectus under Rule 424(b)(3) or other applicable provision of the
Securities Act of 1933 amending the list of selling stockholders to include the pledgee, transferee or other successors in interest
as selling stockholders under this prospectus.


 


The selling stockholders
also may transfer the shares of common stock in other circumstances, in which case the transferees, pledgees or other successors
in interest will be the selling beneficial owners for purposes of this prospectus.


 


The selling stockholders
and any broker-dealers or agents that are involved in selling the shares may be deemed to be "underwriters" within the
meaning of the Securities Act in connection with such sales.  In such event, any commissions received by such broker-dealers
or agents and any profit on the resale of the shares purchased by them may be deemed to be underwriting commissions or discounts
under the Securities Act.  Discounts, concessions, commissions and similar selling expenses, if any, that can be attributed
to the sale of securities will be paid by the selling stockholders and/or the purchasers of the securities.


 


Each selling stockholder
that is affiliated with a registered broker-dealer has confirmed to us that, at the time it acquired the securities subject to
the registration statement of which this prospectus is a part, it did not have any agreement or understanding, directly or indirectly,
with any person to distribute any of such securities.  The Company has advised each selling stockholder that it may not
use shares registered on the registration statement of which this prospectus is a part to cover short sales of our common stock
made prior to the date on which such registration statement was declared effective by the SEC.


 


We are required to pay
certain fees and expenses incident to the registration of the shares.  We have agreed to indemnify the selling stockholders
against certain losses, claims, damages and liabilities, including liabilities under the Securities Act.  We agreed to
keep this prospectus effective until the earlier of (i) the date on which the shares may be resold by the selling stockholders
without registration and without regard to any volume limitations by reason of Rule 144(b)(1) under the Securities Act or any other
rule of similar effect and (ii) such time as all of the shares have been publicly sold.


 




     


     


    

 


Annex B


 


SOLIGENIX, INC.


 


Selling Securityholder Questionnaire


 


The undersigned beneficial owner of shares
of Common Stock (the “Registrable Securities”) of Soligenix, Inc. (the “Company”) understands
that the Company has filed or intends to file with the Securities and Exchange Commission a registration statement (the “Registration
Statement”) for the registration and resale under the Securities Act of 1933, as amended (the “Securities Act”),
of the Registrable Securities.  This Questionnaire is delivered pursuant to the terms of the Registration Rights Agreement
dated as of October , 2017 (the “Registration Rights Agreement”), among the Company and the Investors named
therein.  A copy of the Registration Rights Agreement is available from the Company upon request at the address set forth
below.  All capitalized terms not otherwise defined herein shall have the meanings ascribed thereto in the Registration
Rights Agreement.


 


Certain legal consequences arise from being
named as a selling securityholder in the Registration Statement and the related prospectus. Accordingly, holders and
beneficial owners of Registrable Securities are advised to consult their own securities law counsel regarding the consequences
of being named or not being named as a selling securityholder in the Registration Statement and the related prospectus.


 


The undersigned beneficial owner (the “Selling
Securityholder”) of Registrable Securities hereby elects to include the Registrable Securities owned by it and listed
below in Item 3 (unless otherwise specified under such Item 3) in the Registration Statement.


 


The undersigned hereby provides the following
information to the Company and represents and warrants that such information is accurate:


 


	1.	Name.	 
	 	(a)	Full Legal Name of Selling Securityholder
	 	 	 
	 	 	 
	 	(b)	Full Legal Name of Registered Holder (if not the same as (a) above) through which Registrable Securities Listed in Item 3 below are held:
	 	 	 
	 	 	 
	 	(c)	Full Legal Name of each Control Person (which means a natural person that directly or indirectly has power to vote or dispose of the securities covered by this Questionnaire):
	 	 	 
	 	 	 


 




     


     


    

 


	2.	Address for Notices to Selling Securityholder:


 


	 
	 
	 
	Telephone:	 
	 	 
	 
	 
	Fax:	 
	 	 
	 	 
	Contact Person: 	 
	 	 
	 	 	 	 



	3.	Beneficial Ownership of Registrable Securities:


 


	 	(a)	Type and Principal Amount of Registrable Securities beneficially owned:


 


	 	 
	 	 
	 	 


 


	4.	Broker-Dealer Status:


 


	 	(a)	Are you a broker-dealer?


 


Yes   ☐                      No   ☐


 


	 	Note:	If yes, the Commission’s staff has indicated that you should be identified as an underwriter in the Registration Statement.


 


	 	(b)	Are you an affiliate of a broker-dealer?


 


Yes   ☐                      No   ☐


 


	 	(c)	If you are an affiliate of a broker-dealer, do you certify that you bought the Registrable Securities in the ordinary course of business, and at the time of the purchase of the Registrable Securities to be resold, you had no agreements or understandings, directly or indirectly, with any person to distribute the Registrable Securities?


 


Yes   ☐                      No   ☐


 


	 	Note:	If no, the Commission’s staff has indicated that you should be identified as an underwriter in the Registration Statement.


 






     


     


    

 


	5.	Beneficial Ownership of Other Securities of the Company Owned by the Selling Securityholder.


 


Except as set forth below in this Item
5, the undersigned is not the beneficial or registered owner of any securities of the Company other than the Registrable Securities
listed above in Item 3.


 


	 	(a)	Type and Amount of Other Securities beneficially owned by the Selling Securityholder:


 


	 	 
	 	 


 


	6. 	Relationships with the Company:


 


Except as set forth below, neither the
undersigned nor any of its affiliates, officers, directors or principal equity holders (owners of 5% of more of the equity securities
of the undersigned) has held any position or office or has had any other material relationship with the Company (or its predecessors
or affiliates) during the past three years.


 


	 	State any exceptions here:


 


	 	 
	 	 


 


	7.	Claims against the Company:



 


Except as set forth below, to the actual
knowledge of the officers and directors or persons performing similar functions for the undersigned, neither the undersigned nor
any of its Affiliates, officers, directors or principal equity holders (owners of 5% or more of the equity securities of the undersigned)
has any claims against the Company, its directors, officers, agents and employees, and each Person who controls the Company (within
the meaning of Section 15 of the Securities Act and Section 20 of the Exchange Act) relating to the Company’s sale of Registrable
Securities to the undersigned.


 


State any exceptions here:


 


	 	 
	 	 
	 	 


 


The undersigned agrees to promptly notify
the Company of any inaccuracies or changes in the information provided herein (other than changes in beneficial ownership of Common
Stock after the effectiveness of the Registration Statement) that may occur subsequent to the date hereof at any time prior to
the effectiveness of the Registration Statement or while the Registration Statement remains effective.


 






     


     


    

 


By signing below, the undersigned consents
to the disclosure of the information contained herein in its answers hereto and the inclusion of such information in the Registration
Statement and the related prospectus and any amendments or supplements thereto.  The undersigned understands that such
information will be relied upon by the Company in connection with the preparation or amendment of the Registration Statement and
the related prospectus.


 


IN WITNESS WHEREOF the undersigned, by
authority duly given, has caused this Questionnaire to be executed and delivered either in person or by its duly authorized agent.


 





	Dated:	     	 	Beneficial Owner:	          	 
	 	 	 	 	 	 
	 	 	By:	 	 
	 	 	 	 	 
	 	 	Name:	 	 
	 	 	 	 	 
	 	 	Title:	 	 




 


PLEASE FAX A COPY OF THE COMPLETED AND EXECUTED QUESTIONNAIRE,
AND RETURN THE ORIGINAL BY OVERNIGHT MAIL, TO:


 


Duane Morris LLP


Boca Center Tower II


5100 Town Center Circle, Suite 650


Boca Raton, FL 33486-9000


Attn: Driscoll R. Ugarte


Facsimile: (561) 634-4260