Odyssey Therapeutics, Inc. Schedule 13G shows that Lightspeed-affiliated entities report beneficial ownership of 3,608,443 shares of Odyssey Therapeutics common stock. The filing states this equals 7.6% of the class based on 47,174,156 shares outstanding as of May 11, 2026.
The report lists shared voting and dispositive power for the Lightspeed entities and is filed jointly by Lightspeed Venture Partners XV-B (Ignite), L.P., Lightspeed General Partner XV-B (Ignite), L.P., and Lightspeed Ultimate General Partner XV-B (Ignite), L.L.C.
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Insights
Lightspeed discloses a 7.6% passive stake in Odyssey Therapeutics.
The filing documents that 3,608,443 shares are beneficially owned across Lightspeed XV-B and related entities, with shared voting and dispositive power recorded. The ownership percentage is calculated using May 11, 2026 outstanding shares from a prospectus.
Because this is a Schedule 13G disclosure, it indicates passive investment reporting rather than an active group seeking control; subsequent filings could change this status if the investment intent changes.
Key Figures
Shares beneficially owned:3,608,443 sharesPercent of class:7.6%Shares outstanding:47,174,156 shares+1 more
4 metrics
Shares beneficially owned3,608,443 sharesBeneficial ownership reported by Lightspeed XV-B
Percent of class7.6%Based on 47,174,156 shares outstanding as of <date>May 11, 2026</date>
Shares outstanding47,174,156 sharesIssuer prospectus reported as of <date>May 11, 2026</date>
CUSIP67613T104Odyssey Therapeutics common stock CUSIP shown on filing cover
"Item 1. Name of issuer: Odyssey Therapeutics, Inc.; form_type: SCHEDULE 13G"
A Schedule 13G is a formal document that investors file with the government when they acquire a large ownership stake in a company, usually for investment purposes rather than control. It helps keep the public informed about who owns significant parts of a company's shares, which can influence how the company is managed and how investors make decisions. Filing this schedule is important for transparency and understanding the ownership landscape of publicly traded companies.
beneficially ownedfinancial
"Item 4. Ownership (a) Amount beneficially owned: Row 9 of each Reporting Person's cover page"
Beneficially owned describes securities or assets where a person has the economic rights and control—such as the right to receive dividends and to direct voting—even if legal title is held in another name. Think of it like having the keys and using a car that’s registered to someone else: you get the benefits and make decisions. Investors care because beneficial ownership reveals who truly controls value and voting power, affecting corporate decisions and takeover dynamics.
shared dispositive powerregulatory
"Shared Dispositive Power 3,608,443.00 is listed for the Reporting Persons"
Joint Filing Agreementlegal
"Exhibit 99.1 Joint Filing Agreement"
prospectusregulatory
"based upon 47,174,156 shares outstanding as of May 11, 2026, as reported in the Issuer's prospectus dated May 7, 2026"
A prospectus is a detailed document that explains a company's plans for offering new shares or investments to the public. It’s important because it provides potential investors with key information about the company’s business, risks, and how they might make money, helping them decide whether to invest. Think of it as a guidebook for understanding what you're buying into.
What stake does Lightspeed report in Odyssey Therapeutics (ODTX)?
Lightspeed-affiliated filers report beneficial ownership of 3,608,443 shares, representing 7.6% of the class based on May 11, 2026. The figure is derived from the issuer's prospectus cited in the filing.
Does the Schedule 13G filing show Lightspeed controls Odyssey Therapeutics?
No. The filing reports shared voting and dispositive power but is filed on Schedule 13G, which signals a passive investor intent. It expressly disclaims status as a group for purposes of the form.
What outstanding share count did the filing use for its percentage?
The filing uses 47,174,156 shares outstanding as of May 11, 2026, taken from Odyssey Therapeutics' prospectus dated May 7, 2026 and filed with the SEC on May 8, 2026.
Which entities filed the joint Schedule 13G for Lightspeed?
The joint filing is by Lightspeed Venture Partners XV-B (Ignite), L.P., Lightspeed General Partner XV-B (Ignite), L.P., and Lightspeed Ultimate General Partner XV-B (Ignite), L.L.C., with signatures by Ravi Mhatre.
SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549
SCHEDULE 13G
UNDER THE SECURITIES EXCHANGE ACT OF 1934
Odyssey Therapeutics, Inc.
(Name of Issuer)
Common Stock, $0.0001 par value per share
(Title of Class of Securities)
67613T104
(CUSIP Number)
05/11/2026
(Date of Event Which Requires Filing of this Statement)
Check the appropriate box to designate the rule pursuant to which this Schedule is filed:
Rule 13d-1(b)
Rule 13d-1(c)
Rule 13d-1(d)
schemaVersion:
SCHEDULE 13G
CUSIP Number(s):
67613T104
1
Names of Reporting Persons
Lightspeed Venture Partners XV-B (Ignite), L.P.
2
Check the appropriate box if a member of a Group (see instructions)
(a)
(b)
3
Sec Use Only
4
Citizenship or Place of Organization
DELAWARE
Number of Shares Beneficially Owned by Each Reporting Person With:
5
Sole Voting Power
0.00
6
Shared Voting Power
3,608,443.00
7
Sole Dispositive Power
0.00
8
Shared Dispositive Power
3,608,443.00
9
Aggregate Amount Beneficially Owned by Each Reporting Person
3,608,443.00
10
Check box if the aggregate amount in row (9) excludes certain shares (See Instructions)
11
Percent of class represented by amount in row (9)
7.6 %
12
Type of Reporting Person (See Instructions)
PN
SCHEDULE 13G
CUSIP Number(s):
67613T104
1
Names of Reporting Persons
Lightspeed General Partner XV-B (Ignite), L.P.
2
Check the appropriate box if a member of a Group (see instructions)
(a)
(b)
3
Sec Use Only
4
Citizenship or Place of Organization
DELAWARE
Number of Shares Beneficially Owned by Each Reporting Person With:
5
Sole Voting Power
0.00
6
Shared Voting Power
3,608,443.00
7
Sole Dispositive Power
0.00
8
Shared Dispositive Power
3,608,443.00
9
Aggregate Amount Beneficially Owned by Each Reporting Person
3,608,443.00
10
Check box if the aggregate amount in row (9) excludes certain shares (See Instructions)
11
Percent of class represented by amount in row (9)
7.6 %
12
Type of Reporting Person (See Instructions)
PN
SCHEDULE 13G
CUSIP Number(s):
67613T104
1
Names of Reporting Persons
Lightspeed Ultimate General Partner XV-B (Ignite), L.L.C.
2
Check the appropriate box if a member of a Group (see instructions)
(a)
(b)
3
Sec Use Only
4
Citizenship or Place of Organization
DELAWARE
Number of Shares Beneficially Owned by Each Reporting Person With:
5
Sole Voting Power
0.00
6
Shared Voting Power
3,608,443.00
7
Sole Dispositive Power
0.00
8
Shared Dispositive Power
3,608,443.00
9
Aggregate Amount Beneficially Owned by Each Reporting Person
3,608,443.00
10
Check box if the aggregate amount in row (9) excludes certain shares (See Instructions)
11
Percent of class represented by amount in row (9)
7.6 %
12
Type of Reporting Person (See Instructions)
OO
SCHEDULE 13G
Item 1.
(a)
Name of issuer:
Odyssey Therapeutics, Inc.
(b)
Address of issuer's principal executive offices:
51 Sleeper Street, Suite 800, Boston, MA, 02210 .
Item 2.
(a)
Name of person filing:
The names of the persons filing this report (collectively, the "Reporting Persons") are:
Lightspeed Venture Partners XV-B (Ignite), L.P. ("Lightspeed XV-B")
Lightspeed General Partner XV-B (Ignite), L.P. ("LGP XV-B")
Lightspeed Ultimate General Partner XV-B (Ignite), L.L.C. ("LUGP XV-B")
The Reporting Persons expressly disclaim status as a "group" for purposes of this Schedule 13G.
(b)
Address or principal business office or, if none, residence:
c/o Lightspeed Venture Partners
2200 Sand Hill Road
Menlo Park, CA 94025
If this statement is filed pursuant to §§ 240.13d-1(b) or 240.13d-2(b) or (c), check whether the person filing is a:
(a)
Broker or dealer registered under section 15 of the Act (15 U.S.C. 78o);
(b)
Bank as defined in section 3(a)(6) of the Act (15 U.S.C. 78c);
(c)
Insurance company as defined in section 3(a)(19) of the Act (15 U.S.C. 78c);
(d)
Investment company registered under section 8 of the Investment Company Act of 1940 (15 U.S.C. 80a-8);
(e)
An investment adviser in accordance with § 240.13d-1(b)(1)(ii)(E);
(f)
An employee benefit plan or endowment fund in accordance with § 240.13d-1(b)(1)(ii)(F);
(g)
A parent holding company or control person in accordance with § 240.13d-1(b)(1)(ii)(G);
(h)
A savings associations as defined in Section 3(b) of the Federal Deposit Insurance Act (12 U.S.C. 1813);
(i)
A church plan that is excluded from the definition of an investment company under section 3(c)(14) of the Investment Company Act of 1940 (15 U.S.C. 80a-3);
(j)
A non-U.S. institution in accordance with § 240.13d-1(b)(1)(ii)(J). If filing as a non-U.S. institution in accordance with § 240.13d-1(b)(1)(ii)(J),
please specify the type of institution:
(k)
Group, in accordance with Rule 240.13d-1(b)(1)(ii)(K).
Item 4.
Ownership
(a)
Amount beneficially owned:
Row 9 of each Reporting Person's cover page to this Schedule 13G sets forth the aggregate number of shares of common stock of the Issuer beneficially owned by such Reporting Person and is incorporated by reference.
The Reporting Persons' ownership of the Issuer's securities consists of 3,608,443 shares of common stock directly held by Lightspeed XV-B.
LUGP XV-B serves as the sole general partner of LGP XV-B, which serves as the sole general partner of Lightspeed XV-B.
(b)
Percent of class:
Row 11 of each Reporting Person's cover page to this Schedule 13G sets forth the percentages of the shares of common stock of the Issuer beneficially owned by such Reporting Person and is incorporated by reference. The percentage set forth in each row 11 is based upon 47,174,156 shares of common stock outstanding as of May 11, 2026, as reported in the Issuer's prospectus dated May 7, 2026 filed with the Securities and Exchange Commission (the "SEC") on May 8, 2026.
(c)
Number of shares as to which the person has:
(i) Sole power to vote or to direct the vote:
Row 5 of each Reporting Person's cover page to this Schedule 13G sets forth the sole power to vote or to direct the vote of securities of the Issuer beneficially owned by such Reporting Person and is incorporated by reference.
(ii) Shared power to vote or to direct the vote:
Row 6 of each Reporting Person's cover page to this Schedule 13G sets forth the shared power to vote or to direct the vote of securities of the Issuer beneficially owned by such Reporting Person and is incorporated by reference.
(iii) Sole power to dispose or to direct the disposition of:
Row 7 of each Reporting Person's cover page to this Schedule 13G sets forth the sole power to dispose or to direct the disposition of securities of the Issuer beneficially owned by such Reporting Person and is incorporated by reference.
(iv) Shared power to dispose or to direct the disposition of:
Row 8 of each Reporting Person's cover page to this Schedule 13G sets forth the shared power to dispose or to direct the disposition of securities of the Issuer beneficially owned by such Reporting Person and is incorporated by reference.
Item 5.
Ownership of 5 Percent or Less of a Class.
Not Applicable
Item 6.
Ownership of more than 5 Percent on Behalf of Another Person.
Not Applicable
Item 7.
Identification and Classification of the Subsidiary Which Acquired the Security Being Reported on by the Parent Holding Company or Control Person.
Not Applicable
Item 8.
Identification and Classification of Members of the Group.
Not Applicable
Item 9.
Notice of Dissolution of Group.
Not Applicable
Item 10.
Certifications:
By signing below I certify that, to the best of my knowledge and belief, the securities referred to above were not acquired and are not held for the purpose of or with the effect of changing or influencing the control of the issuer of the securities and were not acquired and are not held in connection with or as a participant in any transaction having that purpose or effect, other than activities solely in connection with a nomination under § 240.14a-11.
SIGNATURE
After reasonable inquiry and to the best of my knowledge and belief, I certify that the information set forth in this statement is true, complete and correct.
Lightspeed Venture Partners XV-B (Ignite), L.P.
Signature:
/s/ Ravi Mhatre
Name/Title:
See Note 1
Date:
05/18/2026
Lightspeed General Partner XV-B (Ignite), L.P.
Signature:
/s/ Ravi Mhatre
Name/Title:
By Lightspeed Ultimate General Partner XV-B (Ignite), L.L.C., its General Partner, By Ravi Mhatre, Managing Member
Date:
05/18/2026
Lightspeed Ultimate General Partner XV-B (Ignite), L.L.C.
Signature:
/s/ Ravi Mhatre
Name/Title:
By Ravi Mhatre, Managing Member
Date:
05/18/2026
Comments accompanying signature: Note 1: By Lightspeed General Partner XV-B (Ignite), L.P., its General Partner, By Lightspeed Ultimate General Partner XV-B (Ignite), L.L.C., its General Partner, By Ravi Mhatre, Managing Member
