Aberdeen Group plc and its affiliate abrdn Inc report beneficial ownership of 1,141,824 shares of Tectonic Therapeutic, Inc. common stock, representing 6.10% of the class as of 12/31/2025.
The firms have shared voting and dispositive power over all of these shares and no sole voting or dispositive authority. They state the position is held in the ordinary course of business and not for the purpose of changing or influencing control of Tectonic Therapeutic.
Positive
None.
Negative
None.
Insights
Institutional investor discloses a 6.1% stake in Tectonic Therapeutic.
Aberdeen Group plc and abrdn Inc report beneficial ownership of 1,141,824 Tectonic Therapeutic common shares, equal to 6.10% of the class as of December 31, 2025. All voting and dispositive authority over these shares is shared, with no sole control.
The disclosure indicates the shares are held in the ordinary course of business and not to change or influence control. This positions the stake as a typical institutional holding rather than an activist one, so implications for corporate strategy or governance appear limited based on the available information.
SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549
SCHEDULE 13G
UNDER THE SECURITIES EXCHANGE ACT OF 1934
Tectonic Therapeutic, Inc.
(Name of Issuer)
Common Stock, $0.0001 par value per share
(Title of Class of Securities)
878972108
(CUSIP Number)
12/31/2025
(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)
SCHEDULE 13G
CUSIP No.
878972108
1
Names of Reporting Persons
Aberdeen Group plc
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
UNITED KINGDOM
Number of Shares Beneficially Owned by Each Reporting Person With:
5
Sole Voting Power
0.00
6
Shared Voting Power
1,141,824.00
7
Sole Dispositive Power
0.00
8
Shared Dispositive Power
1,141,824.00
9
Aggregate Amount Beneficially Owned by Each Reporting Person
1,141,824.00
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)
6.10 %
12
Type of Reporting Person (See Instructions)
HC
SCHEDULE 13G
CUSIP No.
878972108
1
Names of Reporting Persons
abrdn Inc
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
UNITED STATES
Number of Shares Beneficially Owned by Each Reporting Person With:
5
Sole Voting Power
0.00
6
Shared Voting Power
1,141,824.00
7
Sole Dispositive Power
0.00
8
Shared Dispositive Power
1,141,824.00
9
Aggregate Amount Beneficially Owned by Each Reporting Person
1,141,824.00
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)
6.10 %
12
Type of Reporting Person (See Instructions)
CO, IA
SCHEDULE 13G
Item 1.
(a)
Name of issuer:
Tectonic Therapeutic, Inc.
(b)
Address of issuer's principal executive offices:
490 ARSENAL WAY, SUITE 210, WATERTOWN, MASSACHUSETTS
02472
Item 2.
(a)
Name of person filing:
Aberdeen Group plc
abrdn Inc
(b)
Address or principal business office or, if none, residence:
1 George Street
Edinburgh, United Kingdom
EH2 2LL
abrdn Inc
1900 Market Street Suite 200.
Philadelphia
PA 19103
(c)
Citizenship:
Aberdeen Group plc - UNITED KINGDOM
abrdn Inc - UNITED STATES
(d)
Title of class of securities:
Common Stock, $0.0001 par value per share
(e)
CUSIP No.:
878972108
Item 3.
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:
1,141,824
(b)
Percent of class:
6.10 %
(c)
Number of shares as to which the person has:
(i) Sole power to vote or to direct the vote:
Aberdeen Group plc - 0
abrdn Inc - 0
(ii) Shared power to vote or to direct the vote:
Aberdeen Group plc - 1,141,824
abrdn Inc - 1,141,824
(iii) Sole power to dispose or to direct the disposition of:
Aberdeen Group plc - 0
abrdn Inc - 0
(iv) Shared power to dispose or to direct the disposition of:
Aberdeen Group plc - 1,141,824
abrdn Inc - 1,141,824
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.
If a parent holding company has filed this schedule, pursuant to Rule 13d-1(b)(ii)(G), so indicate under Item 3(g) and attach an exhibit stating the identity and the Item 3 classification of the relevant subsidiary. If a parent holding company has filed this schedule pursuant to Rule 13d-1(c) or Rule 13d-1(d), attach an exhibit stating the identification of the relevant subsidiary.
See Exhibit
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 acquired and are held in the ordinary course of business and 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.
Aberdeen Group plc
Signature:
L.Beaton
Name/Title:
Lyn Beaton/ Senior Major Shareholding Reporting Analyst
Date:
01/12/2026
abrdn Inc
Signature:
L.Beaton
Name/Title:
Lyn Beaton/ Senior Major Shareholding Reporting Analyst
Date:
01/12/2026
Exhibit Information
Aberdeen Group plc
abrdn Holdings Limited
abrdn Inc.
Aberdeen Group plc is the parent company.
abrdn Holdings Limited is the intermediate holding company for abrdn Inc.
abrdn Inc. beneficially owns on behalf of our underlying clients 5% or greater of the outstanding shares of the security class being reported on this Schedule 13G.
How many Tectonic Therapeutic (TECX) shares does Aberdeen Group report owning?
Aberdeen Group plc and abrdn Inc report beneficial ownership of 1,141,824 shares of Tectonic Therapeutic common stock. This position represents a 6.10% stake in the company’s outstanding common shares as of December 31, 2025.
What percentage of Tectonic Therapeutic (TECX) does Aberdeen Group control?
Aberdeen Group plc and abrdn Inc collectively report owning 6.10% of Tectonic Therapeutic’s common stock. This percentage is based on 1,141,824 beneficially owned shares relative to the issuer’s outstanding common stock as of December 31, 2025.
Does Aberdeen Group have sole or shared voting power over TECX shares?
Aberdeen Group plc and abrdn Inc report 0 shares with sole voting power and 1,141,824 shares with shared voting power. They likewise hold shared dispositive power over the same shares, indicating joint authority rather than individual control.
Is Aberdeen Group’s TECX stake intended to influence control of the company?
The reporting holders state the Tectonic Therapeutic shares were acquired and are held in the ordinary course of business. They specifically indicate the holdings are not for changing or influencing control or for transactions with that purpose or effect.
Who are the entities reporting ownership in Tectonic Therapeutic (TECX)?
The reporting entities are Aberdeen Group plc, a parent company based in the United Kingdom, and abrdn Inc, its U.S. subsidiary. abrdn Inc is identified as beneficially owning the TECX shares on behalf of underlying clients holding at least 5%.
What role does abrdn Inc play in the reported TECX ownership?
abrdn Inc is described as beneficially owning on behalf of underlying clients 5% or greater of Tectonic Therapeutic’s outstanding common shares. It shares voting and dispositive power over 1,141,824 TECX shares with its parent, Aberdeen Group plc.