Sixth Street Specialty Lending, Inc.
Sixth Street Specialty Lending, Inc. (TSLX) Stock Ownership
Institutional vs insider vs public ownership from 13F and float data — top holders, activity, and insider trades below.
SEC 13F · FMP · TSLX · as of Sep 30, 2025
Ownership Breakdown
254
Institutional Holders
▲ 3 vs Q2
$1.18B
Total Inst. Value
▼ $50.07M vs Q2
95.02M
Shares Outstanding
freeFloat 84.26%
48.74M
13F Shares Held
▼ 136,091 vs Q2
Institutional ownership = 13F shares ÷ total outstanding. Insider % = 100 − free float. Public % = free float − institution %. Data: FMP /symbol-positions-summary + /shares-float + SEC EDGAR.
Top Institutional Holders
TSLX largest shareholders · institutional ownership
Q3 2025 · SEC 13F
Showing top 10 holders
| Holder | Shares | % Owned | Weight | Value | Reported | Change |
|---|---|---|---|---|---|---|
SIXTH STREET PARTNERS MANAGEMENT COMPANY, L.P. | 2.71M | 2.89% | 2.89% | $62.05B | Nov 13, 2025 | — held |
VAN ECK ASSOCIATES CORP | 2.53M | 2.69% | 2.69% | $57.82B | Nov 13, 2025 | ▲ 385.4K |
PROGENY 3, INC. | 2.48M | 2.64% | 2.64% | $56.61B | Nov 14, 2025 | — held |
SOUND INCOME STRATEGIES, LLC | 2.40M | 2.56% | 2.56% | $50.57B | Oct 10, 2025 | ▼ 3.9K |
BURGUNDY ASSET MANAGEMENT LTD. | 2.36M | 2.51% | 2.51% | $57.75B | Nov 12, 2025 | ▼ 16.9K |
STRS OHIO | 2.10M | 2.24% | 2.24% | $48.10B | Oct 30, 2025 | ▼ 1.07M |
MORGAN STANLEY | 2.00M | 2.13% | 2.13% | $45.81B | May 27, 2026 | ▲ 131.3K |
ALLEN INVESTMENT MANAGEMENT LLC | 1.56M | 1.66% | 1.66% | $35.63B | Nov 6, 2025 | ▲ 1.5K |
ARES MANAGEMENT LLC | 1.39M | 1.48% | 1.48% | $31.88B | Nov 14, 2025 | ▼ 7.9K |
UBS GROUP AG | 1.32M | 1.40% | 1.40% | $30.10B | Nov 13, 2025 | ▲ 130.6K |
Data from SEC Form 13F filings. Ownership bar normalised to largest holder. Change flags: isNew / isSoldOut / changeInSharesNumber (FMP extract-analytics/holder).
Institutional Activity
Q3 2025 vs prior quarter
Q3 2025
28
Increased
+2.02M shares2
New Positions
first time holders17
Decreased
−1.80M shares0
Sold Out
fully exitedNet shares change (top 50)
+215.4K
+2.02M / −1.80M
Net new holders
+13
2 new / 0 exited
Based on top 50 institutional holders by position size. Fields: isNew, isSoldOut, changeInSharesNumber (FMP extract-analytics/holder, limit=50).
Insider Buying vs Selling
TSLX insider trading · insider activity
Source: SEC Form 4
Insiders have been net buyers of shares recently. Selling may be driven by pre-scheduled Rule 10b5-1 plans rather than negative sentiment.
2
Buy transactions
0
Sell transactions
0.00
Buy/Sell ratio
$0M
Total disposed
Recent Insider Transactions
Showing 10 most recent · Common Stock only
| Name · Role | Date | Type | Shares | Price | Value | After Trans. | Filing |
|---|---|---|---|---|---|---|---|
Stanley Robert J. CEO | May 28, 2026 | J-Other | 20,000 | $0.01 | $200 | 23.9K | Form 4 ↗ |
Bruck Ross Anthony Vice President | May 11, 2026 | Purchase | 8,000 | $17.76 | $142.1K | 18.3K | Form 4 ↗ |
Covington P Emery director | Mar 6, 2026 | Purchase | 7,500 | $18.35 | $137.6K | 15.0K | Form 4 ↗ |
Waxman Alan Vice President | Mar 6, 2026 | Purchase | 200,000 | $18.42 | $3.68M | 300.0K | Form 4 ↗ |
Waxman Alan Vice President | Mar 5, 2026 | Purchase | 100,000 | $18.46 | $1.85M | 100.0K | Form 4 ↗ |
Stiepleman David Vice President | Mar 2, 2026 | Purchase | 20,200 | $17.65 | $356.5K | 25.7K | Form 4 ↗ |
Peck Joshua Vice President | Mar 2, 2026 | Purchase | 2,840 | $17.59 | $50.0K | 3.1K | Form 4 ↗ |
Pluss Steven Vice President | Feb 27, 2026 | Purchase | 15,000 | $17.72 | $265.8K | 51.5K | Form 4 ↗ |
Graf Michael See Remarks | Feb 26, 2026 | Purchase | 1,000 | $18.26 | $18.3K | 7.2K | Form 4 ↗ |
Stanley Robert J. Co-CEO | Nov 18, 2025 | Purchase | 10,000 | $20.85 | $208.5K | 24.9K | Form 4 ↗ |
Source: /insider-trading/search (FMP stable). Buy/Sell direction: acquisitionOrDisposition A=Buy, D=Sell. RSU vesting (M-Exempt) excluded from sentiment bar. All data from SEC EDGAR public filings.
About institutional & insider ownership
Sixth Street Specialty Lending, Inc. (TSLX) is primarily owned by institutional investors, who hold approximately 51.3% of total shares outstanding. Company insiders own approximately 15.74%, while retail and public investors account for the remaining 32.96%.
The largest institutional shareholder of Sixth Street Specialty Lending, Inc. is SIXTH STREET PARTNERS MANAGEMENT COMPANY, L.P., holding approximately 2.71 million shares — equal to 2.89% of outstanding shares — as of September 30, 2025.
A total of 254 institutional investors currently hold TSLX stock, with a combined institutional value of approximately $1.18 billion as of the most recent 13F filing period.
Frequently asked questions
TSLX ownershipSixth Street Specialty Lending, Inc. (TSLX) is primarily owned by institutional investors, who hold approximately 51.3% of shares. The largest shareholder is SIXTH STREET PARTNERS MANAGEMENT COMPANY, L.P. with a 2.89% stake. Company insiders hold 15.74%. Data sourced from SEC Form 13F as of September 30, 2025.