Amplitude, Inc. — Wellington Management Group LLP and affiliated entities report beneficial ownership of 11,154,556 shares of Amplitude common stock, representing 10.71% of the class. The filing attributes shared voting power of 6,578,413 shares and shared dispositive power across affiliated filers as shown. The Schedule 13G lists the filing entities and describes that the shares are owned of record by clients of Wellington investment advisers; no single client is identified as holding >5%.
Positive
None.
Negative
None.
Insights
Wellington holds a double-digit stake in AMPL via multiple adviser entities.
The filing shows consolidated beneficial ownership of 11,154,556 shares and a 10.71% stake as reported on the cover entries. Ownership is held for clients of several Wellington investment advisers and is reported as shared voting and dispositive power across parent and affiliate entities.
Investor implications depend on portfolio decisions by those clients; subsequent Forms 13D/G or transactions would change the public ownership picture. Further disclosures in future filings could show changes in voting or dispositive arrangements.
Filing structure reflects parent–subsidiary attribution and adviser client ownership.
The Schedule identifies Wellington Management Group LLP, Wellington Group Holdings LLP, Wellington Investment Advisors Holdings LLP, and Wellington Management Company LLP as reporting persons and lists related investment adviser subsidiaries. The filing follows Item 7 instructions describing control and record ownership by clients of the advisers.
Watch for any amendments that convert this passive 13G filing into a 13D or that disclose a single client above 5%; timing and changes will appear in later SEC schedules.
Key Figures
Beneficial ownership:11,154,556 sharesPercent of class:10.71%Shared voting power:6,578,413 shares+2 more
5 metrics
Beneficial ownership11,154,556 sharesConsolidated beneficial ownership reported on Schedule 13G
Percent of class10.71%Percent of Amplitude common stock reported in Item 4(b)
Shared voting power6,578,413 sharesShared voting power reported on cover responses
Shared dispositive power11,154,556 sharesShared dispositive power reported on cover responses
Filing date (signature)04/07/2026Signatures dated on the Schedule 13G
"Identification of the form as Schedule 13G reporting beneficial ownership"
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.
Beneficial ownershipfinancial
"Amount beneficially owned: See the responses to Item 9 on the attached cover pages"
Beneficial ownership means the person or entity that actually enjoys the benefits of owning shares or other assets — such as receiving dividends, voting rights, or price gains — even if the legal title is held in another name. For investors it matters because knowing who truly controls and profits from a company reveals who can influence decisions, exposes potential conflicts of interest or hidden concentration of power, and affects transparency and risk in the stock.
Shared dispositive powerfinancial
"Shared Dispositive Power 11,154,556.00"
Investment adviser clientsregulatory
"owned of record by clients of the Wellington Investment Advisers"
SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549
SCHEDULE 13G
UNDER THE SECURITIES EXCHANGE ACT OF 1934
Amplitude, Inc.
(Name of Issuer)
Common Stock
(Title of Class of Securities)
03213A104
(CUSIP Number)
03/31/2026
(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):
03213A104
1
Names of Reporting Persons
Wellington Management Group LLP
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
MASSACHUSETTS
Number of Shares Beneficially Owned by Each Reporting Person With:
5
Sole Voting Power
0.00
6
Shared Voting Power
6,578,413.00
7
Sole Dispositive Power
0.00
8
Shared Dispositive Power
11,154,556.00
9
Aggregate Amount Beneficially Owned by Each Reporting Person
11,154,556.00
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)
10.7 %
12
Type of Reporting Person (See Instructions)
HC
SCHEDULE 13G
CUSIP Number(s):
03213A104
1
Names of Reporting Persons
Wellington Group Holdings LLP
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
6,578,413.00
7
Sole Dispositive Power
0.00
8
Shared Dispositive Power
11,154,556.00
9
Aggregate Amount Beneficially Owned by Each Reporting Person
11,154,556.00
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)
10.7 %
12
Type of Reporting Person (See Instructions)
HC
SCHEDULE 13G
CUSIP Number(s):
03213A104
1
Names of Reporting Persons
Wellington Investment Advisors Holdings LLP
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
6,578,413.00
7
Sole Dispositive Power
0.00
8
Shared Dispositive Power
11,154,556.00
9
Aggregate Amount Beneficially Owned by Each Reporting Person
11,154,556.00
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)
10.7 %
12
Type of Reporting Person (See Instructions)
HC
SCHEDULE 13G
CUSIP Number(s):
03213A104
1
Names of Reporting Persons
Wellington Management Company LLP
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
6,459,651.00
7
Sole Dispositive Power
0.00
8
Shared Dispositive Power
9,183,551.00
9
Aggregate Amount Beneficially Owned by Each Reporting Person
11,154,556.00
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)
8.8 %
12
Type of Reporting Person (See Instructions)
IA
SCHEDULE 13G
Item 1.
(a)
Name of issuer:
Amplitude, Inc.
(b)
Address of issuer's principal executive offices:
201 3rd Street, Suite 200, San Francisco CA
Item 2.
(a)
Name of person filing:
Wellington Management Group LLP
Wellington Group Holdings LLP
Wellington Investment Advisors Holdings LLP
Wellington Management Company LLP
(b)
Address or principal business office or, if none, residence:
c/o Wellington Management Company LLP, 280 Congress Street, Boston MA 02210
(c)
Citizenship:
Wellington Management Group LLP - Massachusetts
Wellington Group Holdings LLP - Delaware
Wellington Investment Advisors Holdings LLP - Delaware
Wellington Management Company LLP - Delaware
(d)
Title of class of securities:
Common Stock
(e)
CUSIP Number(s):
03213A104
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:
See the responses to Item 9 on the attached cover pages
(b)
Percent of class:
10.71 %
(c)
Number of shares as to which the person has:
(i) Sole power to vote or to direct the vote:
0
(ii) Shared power to vote or to direct the vote:
See the responses to Item 6 on the attached cover pages.
(iii) Sole power to dispose or to direct the disposition of:
0
(iv) Shared power to dispose or to direct the disposition of:
See the responses to Item 8 on the attached cover pages.
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.
If any other person is known to have the right to receive or the power to direct the receipt of dividends from, or the proceeds from the sale of, such securities, a statement to that effect should be included in response to this item and, if such interest relates to more than 5 percent of the class, such person should be identified. A listing of the shareholders of an investment company registered under the Investment Company Act of 1940 or the beneficiaries of employee benefit plan, pension fund or endowment fund is not required.
The securities as to which this Schedule is filed are owned of record by clients of one or more investment advisers identified in Item 7 directly or indirectly owned by Wellington Management Group LLP. Those clients have the right to receive, or the power to direct the receipt of, dividends from, or the proceeds from the sale of, such securities. No such client is known to have such right or power with respect to more than five percent of this class of securities, except as follows:
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.
Pursuant to the instructions in Item 7 of Schedule 13G, the following lists the identity and Item 3 classification of each relevant entity that beneficially owns shares of the security class being reported on this Schedule 13G.
Wellington Group Holdings LLP - HC
Wellington Investment Advisors LLP - HC
Wellington Management Global Holdings, Ltd. - HC
One or more of the following investment advisers (the "Wellington Investment Advisers"):
Wellington Management Company LLP - IA
Wellington Management Canada LLC - IA
Wellington Management Singapore Pte Ltd - IA
Wellington Management Hong Kong Ltd - IA
Wellington Management International Ltd - IA
Wellington Management Japan Pte Ltd - IA
Wellington Management Australia Pty Ltd - IA
The securities as to which this Schedule is filed by Wellington Management Group LLP, as parent holding company of certain holding companies and the Wellington Investment Advisers, are owned of record by clients of the Wellington Investment Advisers. Wellington Investment Advisors Holdings LLP controls directly, or indirectly through Wellington Management Global Holdings, Ltd., the Wellington Investment Advisers. Wellington Investment Advisors Holdings LLP is owned by Wellington Group Holdings LLP. Wellington Group Holdings LLP is owned by Wellington Management Group LLP.
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.
How many Amplitude (AMPL) shares does Wellington beneficially own?
Wellington reports beneficial ownership of 11,154,556 shares. The Schedule 13G lists this consolidated figure and shows the 10.71% ownership percentage reported by the filers.
What percentage of AMPL is owned by Wellington Management Group LLP?
The filing reports a consolidated ownership stake of 10.71% of Amplitude's common stock. The percentage is shown on the cover responses and tied to the 11,154,556 share count.
Who holds voting and dispositive power for the reported shares?
The filing reports shared voting power of 6,578,413 shares and shared dispositive power totaling 11,154,556. Sole voting and dispositive power are reported as 0 for the named entities.
Are the shares held directly by Wellington or by its clients?
The Schedule states the shares are owned of record by clients of Wellington investment advisers. It explains that these clients have the right to receive dividends or sale proceeds, not Wellington directly.
Does any single client hold more than 5% of AMPL under Wellington's filing?
The filing states that no client known to Wellington is identified as holding over 5% of the class, and the response to Item 6 is marked Not Applicable for any >5% client.
