Nuveen Mortgage & Income Fund ownership filing: Sit Investment Associates, Inc. and Sit Fixed Income Advisors II, LLC report shared beneficial ownership of 918,869 shares representing 16.8% of the outstanding common stock. Shares outstanding were 5,476,626 as of December 31, 2025. The filing states the reporting advisers possess shared voting and dispositive power over the securities held by client accounts but disclaim beneficial ownership pursuant to Rule 13d-4.
Positive
None.
Negative
None.
Insights
Large institutional stake reported but held for client accounts; passive disclosure under Schedule 13G/A.
The filing shows two related advisers jointly report 918,869 shares (16.8%) of Nuveen Mortgage & Income Fund based on 5,476,626 shares outstanding as of December 31, 2025. This level typically signals a meaningful institutional position but not an activist posture under Schedule 13G/A norms.
Ownership is disclosed as managed on behalf of client Accounts; subsequent voting or trading activity will depend on adviser decisions and client mandates, timing not specified in the excerpt.
Disclosure follows Section 13 rules and includes a Rule 13d-4 disclaimer.
The filing explicitly cites that SIA and SFI "disclaim beneficial ownership" pursuant to Rule 13d-4, consistent with investment-adviser reporting when holdings are owned by client accounts. The percent calculation is tied to the issuer's Form N-CSR figure for outstanding shares.
Watch for any future amendments or Schedule 13D filings if the advisers change their voting/dispositive stance; timing of any change is not provided in the excerpt.
Key Figures
Reported shares owned:918,869 sharesPercent of class:16.8%Shares outstanding:5,476,626 shares+1 more
4 metrics
Reported shares owned918,869 sharesshared dispositive and voting power reported by SIA/SFI
Percent of class16.8%based on 5,476,626 shares outstanding as of 12/31/2025
Shares outstanding5,476,626 sharesas reported in issuer's Form N-CSR (as of 12/31/2025)
Signature date05/05/2026date signed by Paul E. Rasmussen for both filers
Key Terms
Schedule 13G/A, Rule 13d-4, shared dispositive power
3 terms
Schedule 13G/Aregulatory
"Item 1. (a) Name of issuer: Nuveen Mortgage & Income Fund"
A Schedule 13G/A is an amended public filing with the U.S. securities regulator that updates a previous Schedule 13G, disclosing when an individual or group holds a substantial (typically over 5%) stake in a company and is claiming a passive, non‑controlling intent. Investors monitor these updates because rising or falling holdings can signal changing confidence, potential future moves, or shifts in voting power — like watching a public ledger where large shareholders quietly adjust their positions.
Rule 13d-4regulatory
"Pursuant to Rule 13d-4 of the Securities Exchange Act of 1934"
What stake does Sit Investment Associates report in JLS?
They report shared beneficial ownership of 918,869 shares, equal to 16.8%. This percentage is calculated using 5,476,626 shares outstanding as of December 31, 2025 as stated in the filing.
Do Sit advisors claim direct beneficial ownership of the JLS shares?
No, they expressly disclaim direct beneficial ownership under Rule 13d-4. The advisers state they exercise shared voting and dispositive power on behalf of client Accounts that own the shares.
Which entities filed the Schedule 13G/A for JLS?
The filing names Sit Investment Associates, Inc. and Sit Fixed Income Advisors II, LLC. Addresses and citizenships are provided; SFI is noted as a subsidiary of SIA in the filing.
What outstanding share base was used to compute the 16.8% figure?
The percent is based on 5,476,626 shares outstanding as of December 31, 2025, from the issuer's Form N-CSR cited in the Schedule 13G/A filing.
When was the Schedule 13G/A signed for the JLS filing?
The filing is signed by Paul E. Rasmussen, Vice President, with signature dates of 05/05/2026 for both reporting entities as shown on the form.
SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549
SCHEDULE 13G
UNDER THE SECURITIES EXCHANGE ACT OF 1934
(Amendment No. 8)
Nuveen Mortgage & Income Fund
(Name of Issuer)
Common Stock
(Title of Class of Securities)
670735109
(CUSIP Number)
04/30/2026
(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):
670735109
1
Names of Reporting Persons
Sit Investment Associates, 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
MINNESOTA
Number of Shares Beneficially Owned by Each Reporting Person With:
5
Sole Voting Power
0.00
6
Shared Voting Power
918,869.00
7
Sole Dispositive Power
0.00
8
Shared Dispositive Power
918,869.00
9
Aggregate Amount Beneficially Owned by Each Reporting Person
918,869.00
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)
16.8 %
12
Type of Reporting Person (See Instructions)
IA
SCHEDULE 13G
CUSIP Number(s):
670735109
1
Names of Reporting Persons
Sit Fixed Income Advisors II, LLC
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
918,869.00
7
Sole Dispositive Power
0.00
8
Shared Dispositive Power
918,869.00
9
Aggregate Amount Beneficially Owned by Each Reporting Person
918,869.00
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)
16.8 %
12
Type of Reporting Person (See Instructions)
IA
SCHEDULE 13G
Item 1.
(a)
Name of issuer:
Nuveen Mortgage & Income Fund
(b)
Address of issuer's principal executive offices:
333 West Wacker Drive, Chicago, Illinois 60606
Item 2.
(a)
Name of person filing:
Sit Investment Associates, Inc.
Sit Fixed Income Advisors II, LLC
(b)
Address or principal business office or, if none, residence:
c/o Sit Investment Associates, Inc.
80 South Eighth Street, Suite 3300
Minneapolis, MN 55402
(c)
Citizenship:
Sit Investment Associates, Inc. Minnesota Corporation
Sit Fixed Income Advisors II, LLC Delaware LLC
(d)
Title of class of securities:
Common Stock
(e)
CUSIP No.:
670735109
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 response to item 9 on each cover page.
(b)
Percent of class:
See response to item 11 on each cover page.
(c)
Number of shares as to which the person has:
(i) Sole power to vote or to direct the vote:
See response to item 5 on each cover page.
(ii) Shared power to vote or to direct the vote:
See response to item 6 on each cover page.
(iii) Sole power to dispose or to direct the disposition of:
See response to item 7 on each cover page.
(iv) Shared power to dispose or to direct the disposition of:
See response to item 8 on each cover page.
The ownership percentages reported are based on 5,476,626 shares of common stock outstanding as of December 31, 2025, as reported in the Issuer's Report on Form N-CSR filed with the Securities Exchange Commission.
Sit Investment Associates, Inc. ("SIA") is an investment adviser registered under section 203 of the Investment Advisers Act of 1940. Sit Fixed Income Advisors II, LLC ("SFI") is an investment adviser registered under section 203 of the Investment Advisers Act of 1940 and a subsidiary of SIA. SIA and SFI provide investment management services to client accounts ("Accounts"). In their roles as investment advisers SIA and SFI possess shared voting and investment power over securities of the Issuer described in this schedule 13G owned by the Accounts and may be deemed to be the beneficial owner of such shares of the Issuer owned by the Accounts. All securities reported in this schedule 13G are owned by the Accounts. Pursuant to Rule 13d-4 of the Securities Exchange Act of 1934, as amended (the "Exchange Act"), SIA and SFI disclaim beneficial ownership of such securities.
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 Accounts are 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.
Except as may be indicated if this is a joint filing with a registered investment company managed by SIA or SFI, not more than 5% of the class of such securities is owned by any one Account subject to the investment advice of SIA or SFI.
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 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.
