Ardelyx, Inc.
Ardelyx, Inc. (ARDX) Stock Ownership
Institutional vs insider vs public ownership from 13F and float data — top holders, activity, and insider trades below.
SEC 13F · FMP · ARDX · as of Mar 31, 2025
Ownership Breakdown
230
Institutional Holders
▲ 1 vs Q4
$808.42M
Total Inst. Value
▲ $43.26M vs Q4
247.03M
Shares Outstanding
freeFloat 95.67%
164.58M
13F Shares Held
▲ 13.66M vs Q4
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
ARDX largest shareholders · institutional ownership
Q1 2025 · SEC 13F
Showing top 10 holders
| Holder | Shares | % Owned | Weight | Value | Reported | Change |
|---|---|---|---|---|---|---|
JANUS HENDERSON GROUP PLC pharmaceutical preparations | 24.98M | 10.47% | 10.47% | $122.95B | May 15, 2025 | ▲ 589.1K |
BLACKROCK, INC. pharmaceutical preparations | 17.95M | 7.52% | 7.52% | $88.13B | May 2, 2025 | ▼ 572.8K |
VANGUARD GROUP INC pharmaceutical preparations | 15.00M | 6.28% | 6.28% | $73.64B | May 9, 2025 | ▲ 634.6K |
MACQUARIE GROUP LTD pharmaceutical preparations | 11.16M | 4.68% | 4.68% | $54.79B | Aug 14, 2025 | ▲ 811.5K |
STATE STREET CORP pharmaceutical preparations | 10.18M | 4.26% | 4.26% | $49.97B | May 15, 2025 | ▼ 1.42M |
MARSHALL WACE, LLP pharmaceutical preparations | 8.38M | 3.51% | 3.51% | $41.16B | May 15, 2025 | ▲ 8.27M |
MILLENNIUM MANAGEMENT LLC pharmaceutical preparations | 6.47M | 2.71% | 2.71% | $31.74B | May 15, 2025 | ▲ 3.50M |
GEODE CAPITAL MANAGEMENT, LLC pharmaceutical preparations | 5.67M | 2.38% | 2.38% | $27.86B | May 13, 2025 | ▲ 162.9K |
NUVEEN, LLC pharmaceutical preparations | 3.41M | 1.43% | 1.43% | $16.74B | May 12, 2025 | NEW |
MORGAN STANLEY pharmaceutical preparations | 3.21M | 1.34% | 1.34% | $15.74B | May 15, 2025 | ▲ 784.6K |
Data from SEC Form 13F filings. Ownership bar normalised to largest holder. Change flags: isNew / isSoldOut / changeInSharesNumber (FMP extract-analytics/holder).
Institutional Activity
Q1 2025 vs prior quarter
Q1 2025
33
Increased
+23.68M shares4
New Positions
first time holders12
Decreased
−2.67M shares0
Sold Out
fully exitedNet shares change (top 50)
+21.01M
+23.68M / −2.67M
Net new holders
+25
4 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
ARDX insider trading · insider activity
Source: SEC Form 4
Insiders have been primarily selling shares recently. Selling may be driven by pre-scheduled Rule 10b5-1 plans rather than negative sentiment.
2
Buy transactions
23
Sell transactions
0.09
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 |
|---|---|---|---|---|---|---|---|
Reilly Joseph James See Remarks | May 21, 2026 | Sale | 1,036 | $6.27 | $6.5K | 149.8K | Form 4 ↗ |
Reilly Joseph James See Remarks | May 21, 2026 | Sale | 2,683 | $6.27 | $16.8K | 149.1K | Form 4 ↗ |
Hohenleitner Susan Chief Financial Officer | May 21, 2026 | Sale | 1,455 | $6.27 | $9.1K | 229.1K | Form 4 ↗ |
Bishop John E See Remarks | May 21, 2026 | Sale | 2,306 | $6.27 | $14.5K | 336.8K | Form 4 ↗ |
Brady James Parker Chief Human Resources Officer | May 21, 2026 | Sale | 1,846 | $6.27 | $11.6K | 261.1K | Form 4 ↗ |
Foster Eric Duane Chief Commercial Officer | May 21, 2026 | Sale | 3,166 | $6.27 | $19.8K | 422.8K | Form 4 ↗ |
Foster Eric Duane Chief Commercial Officer | May 21, 2026 | Sale | 2,427 | $6.27 | $15.2K | 420.4K | Form 4 ↗ |
Foster Eric Duane Chief Commercial Officer | May 21, 2026 | Sale | 2,405 | $6.27 | $15.1K | 418.0K | Form 4 ↗ |
Kelliher Mike Chief Business Officer | May 21, 2026 | Sale | 2,900 | $6.27 | $18.2K | 361.8K | Form 4 ↗ |
Kelliher Mike Chief Business Officer | May 21, 2026 | Sale | 1,870 | $6.27 | $11.7K | 359.9K | 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
Ardelyx, Inc. (ARDX) is primarily owned by institutional investors, who hold approximately 66.6% of total shares outstanding. Company insiders own approximately 4.33%, while retail and public investors account for the remaining 29.05%.
The largest institutional shareholder of Ardelyx, Inc. is JANUS HENDERSON GROUP PLC, holding approximately 24.98 million shares — equal to 10.47% of outstanding shares — as of March 31, 2025.
A total of 230 institutional investors currently hold ARDX stock, with a combined institutional value of approximately $808,420,103 as of the most recent 13F filing period.
Frequently asked questions
ARDX ownershipArdelyx, Inc. (ARDX) is primarily owned by institutional investors, who hold approximately 66.6% of shares. The largest shareholder is JANUS HENDERSON GROUP PLC with a 10.47% stake. Company insiders hold 4.33%. Data sourced from SEC Form 13F as of March 31, 2025.