Exhibit 10.10

Execution Version

PATENT SECURITY AGREEMENT

This PATENT SECURITY AGREEMENT (this “Patent Security Agreement”) is made this 9^th day of August, 2018, by and among the Grantors listed on the signature pages hereof (collectively, jointly and severally, “Grantors” and each individually “Grantor”), and DEERFIELD ELGX REVOLVER, LLC, a Delaware limited liability company, in its capacity as agent for each member of the Lender Group (in such capacity, together with its successors and assigns in such capacity, “Agent”).

W I T N E S S E T H:

WHEREAS, pursuant to that certain Credit Agreement dated as of August 9, 2018 (as amended, restated, supplemented, or otherwise modified from time to time, the “Credit Agreement”) by and among ENDOLOGIX, INC., a Delaware corporation (“Endologix”), each of its direct and indirect Subsidiaries set forth on the signature pages thereto and any additional borrower that may thereafter be added to the Credit Agreement (individually as a “Borrower”, and collectively with any entities that become party thereto as Borrower and each of their successors and permitted assigns, the “Borrowers”), the lenders party thereto as “Lenders” (such Lenders, together with their respective successors and assigns in such capacity, each, individually, a “Lender” and, collectively, the “Lenders”), and Agent, the Lender Group has agreed to make certain financial accommodations available to the Borrowers from time to time pursuant to the terms and conditions thereof;

WHEREAS, the members of the Lender Group are willing to make the financial accommodations to the Borrowers as provided for in the Credit Agreement and the other Loan Documents, but only upon the condition, among others, that Grantors shall have executed and delivered to Agent, for the benefit of the Lender Group, that certain Guaranty and Security Agreement, dated as of August 9, 2018 (including all annexes, exhibits or schedules thereto, as from time to time amended, restated, supplemented or otherwise modified, the “Guaranty and Security Agreement”); and

WHEREAS, pursuant to the Guaranty and Security Agreement, Grantors are required to execute and deliver to Agent, for the benefit of the Lender Group, this Patent Security Agreement.

NOW, THEREFORE, in consideration of the premises and mutual covenants herein contained and for other good and valuable consideration, the receipt and sufficiency of which are hereby acknowledged, each Grantor hereby agrees as follows:

1. DEFINED TERMS. All initially capitalized terms used but not otherwise defined herein have the meanings given to them in the Guaranty and Security Agreement or, if not defined therein, in the Credit Agreement, and this Patent Security Agreement shall be subject to the rules of construction set forth in Section 1.04 of the Credit Agreement, which rules of construction are incorporated herein by this reference, mutatis mutandis.

2. GRANT OF SECURITY INTEREST IN PATENT COLLATERAL. Each Grantor hereby unconditionally grants, assigns, and pledges to Agent, for the benefit of each member of the Lender Group, to secure the Secured Obligations, a continuing security interest

1

(referred to in this Patent Security Agreement as the “Security Interest”) in all of such Grantor’s right, title and interest in and to the following, whether now owned or hereafter acquired or arising (collectively, the “Patent Collateral”):

(a) all of its Patents and Patent Intellectual Property Licenses to which it is a party including those referred to on Schedule I;

(b) all divisionals, continuations, continuations-in-part, reissues, reexaminations, or extensions of the foregoing; and

(c) all products and proceeds of the foregoing, including any claim by such Grantor against third parties for past, present or future infringement of any Patent or any Patent exclusively licensed under any Intellectual Property License, including the right to receive damages, or right to receive license fees, royalties, and other compensation under any Patent Intellectual Property License.

3. SECURITY FOR SECURED OBLIGATIONS. This Patent Security Agreement and the Security Interest created hereby secures the payment and performance of the Secured Obligations, whether now existing or arising hereafter. Without limiting the generality of the foregoing, this Patent Security Agreement secures the payment of all amounts which constitute part of the Secured Obligations and would be owed by Grantors, or any of them, to Agent, the other members of the Lender Group or any of them, whether or not they are unenforceable or not allowable due to the existence of an Insolvency Proceeding involving any Grantor.

4. PROTECTION OF PATENT SECURITY INTEREST BY GRANTORS. Each Grantor shall, at its sole cost, expense and risk, in connection with the operation of its business, comply with the requirements set forth in Section 6 of the Guaranty and Security Agreement in respect of the Patent Collateral.

5. REPRESENTATIONS AND WARRANTIES. Each Grantor represents and warrants that:

(a) Schedule I hereto is a true, correct and complete list of all Patents and Patent Intellectual Property Licenses in which each Grantor purports to have an ownership or license interest.

(b) Such Grantor has the legal right and authority to enter into this Patent Security Agreement and perform its terms.

(c) If such Grantor amends its name, such Grantor shall provide copies of such amendment documentation to Agent and shall, if necessary, re-register such Grantor’s Patents and Patent Intellectual Property Licenses with the appropriate Governmental Authority and shall execute and deliver such agreements or documentation as Agent shall reasonably request in writing to maintain a perfected first priority security interest in the Patent Collateral subject to Permitted Liens.

6. SECURITY AGREEMENT. The Security Interest in the Collateral granted pursuant to this Patent Security Agreement is granted in conjunction with the security interests

2

granted to Agent, for the benefit of the Lender Group, pursuant to the Guaranty and Security Agreement. Each Grantor hereby acknowledges and affirms that the rights and remedies of Agent with respect to the Security Interest in the Patent Collateral made and granted hereby are more fully set forth in the Guaranty and Security Agreement, the terms and provisions of which are incorporated by reference herein as if fully set forth herein. To the extent there is any inconsistency between this Patent Security Agreement and the Guaranty and Security Agreement, the Guaranty and Security Agreement shall control.

7. AUTHORIZATION TO SUPPLEMENT. If any Grantor shall obtain rights to any new patent application or issued patent or become entitled to the benefit of any patent application or patent for any divisional, continuation, continuation-in-part, reissue, or reexamination of any existing patent or patent application, the provisions of this Patent Security Agreement shall automatically apply thereto. Each Grantor shall notify Agent of applications filed for the registration of any Patents with the United States Patent Office in accordance with Section 5.7(g) of the Guaranty and Security Agreement. Without limiting Grantors’ obligations under this Section, Grantors hereby authorize Agent unilaterally to modify this Patent Security Agreement by amending Schedule I to include any such new patent rights of each Grantor. Notwithstanding the foregoing, no failure to so modify this Patent Security Agreement or amend Schedule I shall in any way affect, invalidate or detract from Agent’s continuing security interest in all Collateral, whether or not listed on Schedule I.

8. NO VIOLATION OF LOAN DOCUMENTS. The representations, warranties or covenants contained herein are supplemental to those representations, warranties and covenants contained in the other Loan Documents, and shall not be deemed to modify any such representation, warranty or covenant contained in any other Loan Document.

9. GRANTOR’S RIGHTS TO ENFORCE PATENTS. Prior to Agent’s giving of notice to Grantor following the occurrence and during the continuance of an Event of Default, such Grantor shall have the exclusive right to sue for past, present and future infringement of the Patent Collateral, including the right to seek injunctions and/or money damages, in an effort by such Grantor to protect the Patent Collateral against encroachment by third parties, provided, however, that:

(a) Any money damages awarded or received by such Grantor on account of such suit (or the threat of such suit) shall constitute Patent Collateral.

(b) Any damages recovered in any action pursuant to this Section, net of costs and attorneys’ fees reasonably incurred, shall be applied in accordance with the Credit Agreement and the Guaranty and Security Agreement.

(c) Following the occurrence and during the continuance of any Event of Default, Agent, by notice to any Grantor may terminate or limit such Grantor’s rights under this Section 9.

10. RIGHTS UPON DEFAULT. Upon the occurrence and during the continuance of any Event of Default, Agent may exercise all rights and remedies as provided for in the Guaranty and Security Agreement.

3

11. NO LIMITATION; LOAN DOCUMENTS. This Patent Security Agreement has been executed and delivered by each Grantor for the purpose of recording the security interest granted to Agent with respect to the Patent Collateral with the United States Patent Office. The security interest granted hereby has been granted as a supplement to, and not in limitation of, the security interest granted to Agent, for the benefit of the Lender Group, under the Guaranty and Security Agreement and the other Loan Documents. The other Loan Documents (and all rights and remedies of Grantor, Agent, and Lenders thereunder) shall remain in full force and effect in accordance with their terms.

12. TERMINATION; RELEASE OF PATENT COLLATERAL. This Patent Security Agreement and all obligations of each Grantor and Agent hereunder shall terminate on the date upon which the Obligations have been Paid in Full. Upon termination of this Patent Security Agreement, Agent shall, at the reasonable expense of the Grantor, take such actions required by the Credit Agreement or the Guaranty and Security Agreement or as otherwise reasonably requested by Grantor to release its security interest in the Patent Collateral.

13. BINDING EFFECT; BENEFITS. This Patent Security Agreement shall be binding upon each Grantor and its successors and assigns, and shall inure to the benefit of Agent, Lenders and their respective successors and assigns.

14. COUNTERPARTS. This Patent Security Agreement is a Loan Document. This Patent Security Agreement may be executed in any number of counterparts and by different parties on separate counterparts, each of which, when executed and delivered, shall be deemed to be an original, and all of which, when taken together, shall constitute but one and the same Patent Security Agreement. Delivery of an executed counterpart of this Patent Security Agreement by telefacsimile or other electronic method of transmission shall be equally as effective as delivery of an original executed counterpart of this Patent Security Agreement. Any party delivering an executed counterpart of this Patent Security Agreement by telefacsimile or other electronic method of transmission also shall deliver an original executed counterpart of this Patent Security Agreement but the failure to deliver an original executed counterpart shall not affect the validity, enforceability, and binding effect of this Patent Security Agreement.

15. CHOICE OF LAW AND VENUE, JURY TRIAL WAIVER, AND JUDICIAL REFERENCE PROVISION. THIS PATENT SECURITY AGREEMENT SHALL BE SUBJECT TO THE PROVISIONS REGARDING CHOICE OF LAW AND VENUE, JURY TRIAL WAIVER, AND JUDICIAL REFERENCE SET FORTH IN SECTIONS 8.11 AND 8.12 OF THE GUARANTY AND SECURITY AGREEMENT, AND SUCH PROVISIONS ARE INCORPORATED HEREIN BY THIS REFERENCE, MUTATIS MUTANDIS.

[signature page follows]

4

IN WITNESS WHEREOF, the parties hereto have caused this Patent Security Agreement to be executed and delivered as of the day and year first above written.

[SIGNATURE PAGE TO PATENT SECURITY AGREEMENT]

IN WITNESS WHEREOF, the parties hereto have caused this Patent Security Agreement to be executed and delivered as of the day and year first above written.

6

SCHEDULE I

to

PATENT SECURITY AGREEMENT

Patents

2

3

4

5

6

7

8

9

10

11

12

13

14

15

16

17

18

19

20

21

22

23

24

25

26

27

28

29

30

31

32

33

34

35

36

37

38

39

40

41

42

43

44

45

46

47

48

49

50

51