Nephros (NEPH)

Nephros on one page: short interest, daily short volume, fails to deliver, large holders, 13F holders, earnings dates and insider trades. Listed on Nasdaq, classified by the SEC as surgical & medical instruments & apparatus.

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15K

Short interest

settlement 2026-10-15

1.0

Days to cover

-0.4 days vs prior

23.5%

Short share of volume

2026-11-02

144

Fails to deliver

settlement 2026-09-14

Wed 11 Nov

Next earnings

estimated date

Insider flow, 90 days

0 buys, 0 sells

As of 2026-11-02.

Short interest

FINRA, twice a month. The newest 48 settlements in the table, 48 in the chart. JSON

As of 15 October 2026, short interest in NEPH is 15,442 shares, down 30,958 shares over the last month. Over the last 48 readings it ranged from 3,237 shares (15 May 2025) to 46,667 shares (31 March 2026). At the reported average volume of 54K shares a day that is 1.0 days to cover.

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Settlement	Shares short	Change	Avg daily volume	Days to cover
2026-10-15	15,442	-39.0%	54,352	1.00
2026-09-30	25,302	-45.5%	18,272	1.38
2026-09-15	46,400	+13.3%	22,590	2.05
2026-08-31	40,967	-8.5%	41,602	1.00
2026-08-14	44,763	+19.4%	26,956	1.66
2026-07-31	37,493	+19.6%	8,972	4.18
2026-07-15	31,336	-1.5%	9,435	3.32
2026-06-30	31,812	+59.6%	12,792	2.49
2026-06-15	19,933	-21.2%	11,605	1.72
2026-05-29	25,295	+19.4%	27,817	1.00
2026-05-15	21,191	-28.9%	40,627	1.00
2026-04-30	29,811	-28.1%	24,100	1.24
2026-04-15	41,492	-11.1%	22,090	1.88
2026-03-31	46,667	+762.0%	59,824	1.00
2026-03-13	5,414	+28.8%	35,028	1.00
2026-02-27	4,205	-57.8%	46,029	1.00
2026-02-13	9,959	+0.6%	43,680	1.00
2026-01-30	9,897	+32.0%	44,093	1.00
2026-01-15	7,496	-11.3%	55,842	1.00
2025-12-31	8,451	+133.1%	40,853	1.00
2025-12-15	3,625	-49.9%	67,084	1.00
2025-11-28	7,233	+13.2%	82,838	1.00
2025-11-14	6,391	-35.8%	72,512	1.00
2025-10-31	9,961	+51.4%	64,298	1.00
2025-10-15	6,580	+32.0%	99,231	1.00
2025-09-30	4,983	-69.8%	60,884	1.00
2025-09-15	16,506	+324.1%	61,763	1.00
2025-08-29	3,892	-43.8%	38,558	1.00
2025-08-15	6,922	+51.9%	66,464	1.00
2025-07-31	4,556	+20.6%	16,794	1.00
2025-07-15	3,779	+5.9%	36,320	1.00
2025-06-30	3,569	-44.4%	82,936	1.00
2025-06-13	6,420	+25.3%	53,716	1.00
2025-05-30	5,122	+58.2%	34,459	1.00
2025-05-15	3,237	-60.0%	9,494	1.00
2025-04-30	8,083	-29.3%	4,157	1.94
2025-04-15	11,427	-45.6%	15,828	1.00
2025-03-31	21,018	+8.5%	9,689	2.17
2025-03-14	19,379	+132.3%	15,367	1.26
2025-02-28	8,342	-12.9%	14,179	1.00
2025-02-14	9,574	+90.8%	26,672	1.00
2025-01-31	5,018	-29.9%	9,804	1.00
2025-01-15	7,163	+66.4%	8,521	1.00
2024-12-31	4,305	-11.4%	9,757	1.00
2024-12-13	4,861	-36.5%	6,808	1.00
2024-11-29	7,656	-0.5%	12,204	1.00
2024-11-15	7,693	-30.5%	9,735	1.00
2024-10-31	11,075	+1669.2%	7,694	1.44

Daily short volume

FINRA Reg SHO, the last 30 sessions. JSON

As of 2 November 2026, the short share of NEPH volume is 23.5%, down 3.1 points over the last five sessions. Over the last 30 readings it ranged from 1.5% (28 October 2026) to 63.3% (19 October 2026). The latest reading is 5.2 points below the 30-session average of 28.7%, on 14K shares reported.

Date	Short volume	Total volume	Short share	Exempt
2026-11-02	3K	14K	23.5%	0
2026-10-30	3K	9K	27.6%	0
2026-10-29	1K	18K	5.7%	611
2026-10-28	2K	128K	1.5%	125
2026-10-27	281	16K	1.8%	0
2026-10-26	4K	14K	26.6%	0
2026-10-23	8K	22K	38.5%	0
2026-10-22	651	3K	22.2%	0
2026-10-21	1K	8K	12.9%	0
2026-10-20	4K	13K	27.3%	0
2026-10-19	7K	11K	63.3%	0
2026-10-16	6K	15K	41.8%	0
2026-10-15	6K	11K	48.7%	0
2026-10-14	1K	4K	33.5%	0
2026-10-13	4K	15K	27.5%	600
2026-10-12	5K	24K	22.9%	1,227
2026-10-09	14K	27K	51.4%	0
2026-10-08	24K	45K	52.9%	0
2026-10-07	8K	21K	39.1%	800
2026-10-06	5K	69K	6.6%	0
2026-10-05	2K	6K	36.3%	0
2026-10-02	377	7K	5.4%	0
2026-10-01	3K	18K	16.2%	0
2026-09-30	252	4K	6.1%	0
2026-09-29	6K	15K	38.9%	0
2026-09-28	4K	8K	56.8%	2,830
2026-09-25	2K	5K	30.9%	0
2026-09-24	221	877	25.2%	0
2026-09-23	417	2K	26.8%	0
2026-09-22	6K	15K	42.6%	0

Fails to deliver

SEC, the last 30 settlement dates with a fail. JSON

As of 14 September 2026, the fails-to-deliver balance in NEPH is 144 shares, up 23 shares over the last settlement date. Over the last 30 readings it ranged from 1 share (10 July 2026) to 4,434 shares (18 September 2025). The latest reading sits at the bottom of that range.

Settlement	Shares failed	Price	Value
2026-09-14	144	$4.47	$644
2026-09-11	121	$4.52	$547
2026-08-31	1,509	$4.55	$7K
2026-08-04	1,317	$3.51	$5K
2026-07-10	1	$3.50	$4
2026-07-01	23	$3.57	$82
2026-06-04	961	$3.64	$3K
2026-04-06	3,862	$2.87	$11K
2026-03-12	96	$3.93	$377
2026-02-10	1,000	$4.02	$4K
2026-01-20	555	$4.48	$2K
2025-12-29	1,000	$4.93	$5K
2025-11-10	931	$4.60	$4K
2025-11-06	1,612	$5.69	$9K
2025-10-31	3,582	$5.61	$20K
2025-10-23	983	$4.80	$5K
2025-10-14	1,810	$5.34	$10K
2025-10-06	1,204	$4.77	$6K
2025-10-03	951	$4.64	$4K
2025-10-01	518	$4.73	$2K
2025-09-24	799	$4.25	$3K
2025-09-19	2,241	$4.06	$9K
2025-09-18	4,434	$4.27	$19K
2025-09-17	4,403	$4.31	$19K
2025-09-16	2,193	$4.36	$10K
2025-09-12	2,484	$4.21	$10K
2025-09-11	984	$4.21	$4K
2025-09-09	347	$3.93	$1K
2025-08-12	127	$4.49	$570
2025-07-16	9	$3.53	$32

Insider trades

SEC Form 4, newest first. JSON

No open-market insider trades were reported for NEPH in the last 90 days. The most recent filings are listed below. Latest filing: WEXFORD CAPITAL LP (10% owner) on 2026-09-14.

Date	Insider	Title	Type	Shares	Price	Value	Owned after
2026-09-14	WEXFORD CAPITAL LP	10% owner	Other transaction	23K	$3.95	$90K	167K
2026-09-14	WEXFORD CAPITAL LP	10% owner	Other transaction	3.4M	$0.00	$0	189K
2026-09-14	Amron Arthur H	Director	Other transaction	23K	$3.95	$90K	26K
2026-09-14	Amron Arthur H	Director	Other transaction	3K	$0.00	$0	3K
2026-09-14	Amron Arthur H	Director	Other transaction	18K	$0.00	$0	159K
2026-08-18	WEXFORD CAPITAL LP	10% owner	Exercise or conversion	812	$3.60	$3K	57K
2026-08-12	Amron Arthur H	Director	Grant	2K	$0.00	$0	141K
2026-05-11	Amron Arthur H	Director	Grant	4K	$0.00	$0	138K
2026-03-23	Krandel Judy	Chief Financial Officer	Exercise or conversion	69K	$1.71	$118K	69K
2026-03-23	Banks Robert R. Jr.	President and CEO	Exercise or conversion	120K	$1.44	$173K	190K
2026-03-16	Amron Arthur H	Director	Grant	4K	$0.00	$0	135K
2025-11-10	Nettis Lisa Marie	Director	Grant	2K	$0.00	$0	2K
2025-11-10	Spandow Oliver J.	Director	Grant	8K	$0.00	$0	123K
2025-11-10	Amron Arthur H	Director	Grant	5K	$0.00	$0	131K
2025-01-01	Spandow Oliver J.	Director	Grant	33K	$0.00	$0	115K
2025-01-01	Amron Arthur H	Director	Grant	22K	$0.00	$0	126K
2024-05-30	Amron Arthur H	Director	Buy	3K	$2.24	$7K	103K
2024-05-28	Amron Arthur H	Director	Buy	2K	$2.22	$4K	100K
2024-05-16	Banks Robert R. Jr.	President and CEO	Buy	50K	$2.24	$112K	70K
2024-03-13	Amron Arthur H	Director	Other transaction	91K	$0.00	$0	98K
2024-03-13	Wexford GP LLC	TenPercentOwner	Other transaction	91K	$0.00	$0	56K
2024-03-12	Amron Arthur H	Director	Buy	7K	$2.45	$17K	7K
2023-12-13	Amron Arthur H	Director	Grant	9K	$0.00	$0	9K
2023-12-13	Harris Joseph Michael	Director	Grant	9K	$0.00	$0	18K
2023-12-13	Lask Alisa	Director	Grant	9K	$0.00	$0	49K
2023-12-13	Spandow Oliver J.	Director	Grant	14K	$0.00	$0	82K
2023-12-07	Banks Robert R. Jr.	President and CEO	Buy	18K	$2.20	$40K	20K
2023-08-15	Banks Robert R. Jr.	President and CEO	Buy	2K	$1.69	$3K	2K
2023-08-14	Banks Robert R. Jr.	President and CEO	Buy	99	$1.50	$149	99
2023-01-05	Harris Joseph Michael	Director	Grant	8K	$0.00	$0	8K
2023-01-05	Amron Arthur H	Director	Grant	28K	$0.00	$0	28K
2023-01-05	Gwydir Tom	Director	Grant	28K	$0.00	$0	43K
2023-01-05	Spandow Oliver J.	Director	Grant	42K	$0.00	$0	67K
2023-01-05	Lask Alisa	Director	Grant	28K	$0.00	$0	39K
2022-03-05	Astor Andrew	President, CEO & CFO	Exercise or conversion	15K	$2.70	$40K	93K
2022-02-16	Lobo Wesley S.	Chief Marketing Officer	Tax withholding	6K	$4.80	$31K	35K
2021-12-14	Unknown	Director	Grant	5K	$0.00	$0	5K
2021-12-14	Spandow Oliver J.	Director	Grant	5K	$0.00	$0	25K
2021-12-14	Gwydir Tom	Director	Grant	5K	$0.00	$0	16K
2021-12-14	Unknown	Director	Grant	5K	$0.00	$0	12K
2021-08-20	Lobo Wesley S.	Chief Marketing Officer	Buy	1K	$7.92	$8K	42K
2021-08-18	Astor Andrew	President & CEO	Buy	3K	$7.77	$19K	78K
2021-08-18	Gwydir Tom	Director	Buy	5K	$7.64	$38K	11K
2021-08-17	Astor Andrew	President & CEO	Buy	3K	$7.67	$19K	75K
2021-06-01	WEXFORD CAPITAL LP	Director,TenPercentOwner	Exercise (in or at the money)	67K	$2.70	$180K	3.5M
2021-05-27	Evans Daron	CEO Specialty Renal Products	Tax withholding	349	$2.70	$942	9K
2021-05-24	Evans Daron	CEO of Specialty Renal Product	Exercise (in or at the money)	1K	$2.70	$3K	9K
2021-05-24	Evans Daron	CEO of Specialty Renal Product	Exercise (in or at the money)	1K	$2.70	$3K	9K
2021-02-16	Lobo Wesley S.	Chief Marketing Officer	Grant	41K	$0.00	$0	41K
2021-01-27	Wexford GP LLC	Director,TenPercentOwner	Exercise or conversion	3K	$4.14	$12K	98K
2021-01-27	Wexford GP LLC	Director,TenPercentOwner	Exercise or conversion	4K	$3.60	$14K	102K
2021-01-27	Wexford GP LLC	Director,TenPercentOwner	Exercise or conversion	4K	$4.50	$20K	106K
2021-01-27	Wexford GP LLC	Director,TenPercentOwner	Exercise or conversion	4K	$4.59	$16K	95K
2021-01-06	AMRON ARTHUR H	Director	Grant	4K	$0.00	$0	4K
2021-01-06	Spandow Oliver J.	Director	Grant	4K	$0.00	$0	19K
2021-01-06	PERSEN MALCOLM C	Director	Grant	6K	$0.00	$0	49K
2021-01-06	Lask Alisa	Director	Grant	4K	$0.00	$0	7K
2021-01-06	Gwydir Tom	Director	Grant	4K	$0.00	$0	6K
2021-01-06	DAVIDSON CHARLES E	Director,TenPercentOwner	Grant	3K	$0.00	$0	3K
2020-11-19	Astor Andrew	President & CEO	Buy	1K	$5.87	$6K	73K
2020-11-18	Spandow Oliver J.	Director	Buy	2K	$5.83	$9K	16K
2020-10-15	DAVIDSON CHARLES E	Director,TenPercentOwner	Grant	167K	$6.00	$1.0M	3.6M
2020-08-19	Astor Andrew	COO/CFO	Buy	950	$7.40	$7K	72K
2020-05-28	Astor Andrew	CFO/COO	Buy	1K	$6.96	$7K	71K
2020-05-11	PERSEN MALCOLM C	Director	Exercise (in or at the money)	2K	$7.65	$13K	5K
2020-03-12	Astor Andrew	CFO/COO	Buy	1K	$6.70	$7K	70K
2020-03-12	Evans Daron	President and CEO	Buy	3K	$6.65	$17K	134K
2020-03-05	Astor Andrew	CFO/COO	Buy	700	$8.46	$6K	69K
2020-03-05	Evans Daron	President and CEO	Buy	3K	$8.44	$21K	132K

Form 4 filings are due within two business days of the trade. Insiders sell for many reasons that say nothing about the company; open-market buys are rarer.

Large holders (13D and 13G)

One row per reporting person with its latest filing, newest first. JSON

4 holders report 5% or more of NEPH in their latest filing, all on Schedule 13G (passive). The largest reported stake is CD Holding Company, LLC at 5.7% of the class (616,945 shares), filed 2026-09-16 for an event on 2026-09-14.

Filed	Form	Holder	Shares	Of class	Event
2026-09-16	13D/Ano. 12	Joseph M. Jacobsindividual	224K	2.1%	2026-09-14
2026-09-16	13D/Ano. 12	Charles E. Davidsonindividual	224K	2.1%	2026-09-14
2026-09-16	13D/Ano. 12	Wexford GP LLCother entity	224K	2.1%	2026-09-14
2026-09-16	13D/Ano. 12	Wexford Capital LPpartnership	224K	2.1%	2026-09-14
2026-09-16	13G	CD Holding Company, LLCother entity	617K	5.7%	2026-09-14
2025-11-14	13G	Topline Capital Management, LLCinvestment adviser	595K	5.6%	2025-08-04
2025-11-14	13G	Collin McBirneyindividual, parent holding company	595K	5.6%	2025-08-04
2025-11-14	13G	Topline Capital Partners, LPpartnership	595K	5.6%	2025-08-04

13F holders

Tracked managers holding NEPH at their latest 13F. JSON

2 of the 30 tracked managers held NEPH at their latest 13F, $380K in total at quarter-end prices. Renaissance Technologies is the largest at $277K (0.0% of its portfolio) as of 2026-06-30. Over the prior quarter 1 added shares and 1 cut.

Fund	Quarter	Shares	Value	Of portfolio	Change in shares
Renaissance Technologies	2026-06-30	78K	$277K	0.00%	-22K
Citadel Advisors	2026-06-30	29K	$104K	0.00%	+8K

Only the 30 tracked managers on the funds hub; a 13F reports long positions in US listed stock at quarter end, 45 days late, and says nothing about shorts or positions sold since.

What this page is

Nephros in the regulatory record

Regulators publish company data in separate files that never sit next to each other: FINRA's twice-monthly short interest, its daily short sale volume, the SEC's fails-to-deliver counts, and each insider's Form 4. A company page puts those series for one ticker on one URL, with planned sales, large holders, 13F holders and financials beside them, so the short position, the daily flow, the settlement fails and what insiders are doing can be read together.

Each section has its own history table, a one-line summary of the latest figures and its own JSON and CSV links, and says when its source last updated.

This page follows Nephros (NEPH), SEC CIK 1196298, listed on Nasdaq, classified by the SEC as surgical & medical instruments & apparatus. The cross-market tables live on the short interest and insider transactions hubs.

Source and updates

Short interest: FINRA consolidated short interestSource: FINRA.Twice a month, about eight business days after settlement. Latest 2026-10-15.JSON and CSV
Daily short volume: FINRA Reg SHO daily filesSource: FINRA.Every trading day, the morning after FINRA posts it. Latest 2026-11-02.JSON and CSV
Fails to deliver: SEC fails-to-deliver dataSource: SEC.Twice a month, a few weeks after the half month ends. Latest 2026-09-14.JSON and CSV
Large holders: SEC EDGAR Schedule 13D and 13GSource: SEC.New filings appear shortly after the SEC posts them. A 13D is due within five business days of crossing 5%; a 13G follows the passive schedule. Latest 2026-09-16.JSON and CSV
13F holders: SEC EDGAR Form 13F-HRSource: SEC.Quarterly, filed within 45 days of quarter end; 30 tracked managers. Latest 2026-06-30.JSON and CSV
Earnings dates: SEC EDGAR 8-K filings (Item 2.02)Source: SEC.Twice a day. Reported dates come from the company's 8-K filings; the next date is marked as an estimate until the 8-K arrives. Latest 2026-08-06.JSON and CSV
Insider trades: SEC EDGAR Form 4Source: SEC.New filings appear shortly after the SEC posts them; they're due two business days after the trade. Latest 2026-09-14.JSON and CSV
Company record: EDGAR filing index for CIK 1196298Ticker, name and exchange from the SEC's company list, refreshed weekly.
Rate limits: 10 requests a minute without a key, 30 with a free key from a free account.

How to read it

Read the position against the flow: rising short interest with a high daily short share is new shorting; rising short interest with a normal short share is old shorts holding on.
Insider buys next to a large short position are rare and stand out; insider sells next to one are common and mean little.
Fails to deliver matter relative to the float, not in absolute shares; a million failed shares in a mega cap is noise.

Analysis of what the data shows, not advice. XOOMAR does not recommend buying, selling or holding anything.

Other companies the SEC classifies as surgical & medical instruments & apparatus

Other company pages

Datasets

Frequently Asked Questions

How much of NEPH is sold short?

15,442 shares were held short at the 2026-10-15 settlement, 1.0 days of average volume. FINRA publishes the next count about eight business days after the 15th and the last business day of the month.

What is NEPH's daily short volume?

On 2026-11-02, 3,329 of the 14,172 NEPH shares reported to FINRA were sold short, 23.5% of the day's reported volume. Short volume is a flow for one day, not a position.

Does NEPH have fails to deliver?

The SEC's latest file shows 144 NEPH shares failed to deliver at settlement 2026-09-14. Fails are reported per settlement date and published twice a month with a lag.

Are NEPH insiders buying or selling?

No open-market insider trades were reported for NEPH in the last 90 days. The most recent filings are listed below. Latest filing: WEXFORD CAPITAL LP (10% owner) on 2026-09-14.

Who owns 5% or more of NEPH?

Which tracked 13F managers own NEPH?

2 of the 30 tracked 13F managers held NEPH shares at their latest filing, $380K in all. The largest: Renaissance Technologies (78K shares, $277K), Ken Griffin's Citadel Advisors (29K shares, $104K).

Data on this page is provided for informational purposes only and is not financial advice. See our editorial policy.