Mplx (MPLX)

Mplx on one page: short interest, daily short volume, fails to deliver, 13F holders, financials, earnings dates and insider trades. Listed on NYSE, classified by the SEC as pipe lines (no natural gas).

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6.7M

Short interest

settlement 2026-09-30

4.2

Days to cover

-1.2 days vs prior

61.2%

Short share of volume

2026-10-12

1,469

Fails to deliver

settlement 2026-09-08

Tue 3 Nov

Next earnings

estimated date

Insider flow, 90 days

0 buys, 0 sells

As of 2026-10-12.

Short interest

FINRA, twice a month. The newest 24 settlements in the table, 48 in the chart. JSON

As of 30 September 2026, short interest in MPLX is 6,685,785 shares, down 660,512 shares over the last month. Over the last 48 readings it ranged from 5,979,529 shares (30 June 2026) to 11,419,731 shares (29 November 2024). At the reported average volume of 1.6M shares a day that is 4.2 days to cover.

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Settlement	Shares short	Change	Avg daily volume	Days to cover
2026-09-30	6,685,785	+0.8%	1,585,369	4.22
2026-09-15	6,632,787	-9.7%	1,230,174	5.39
2026-08-31	7,346,297	-1.5%	1,054,181	6.97
2026-08-14	7,459,259	-2.9%	1,580,455	4.72
2026-07-31	7,680,934	+8.1%	1,703,801	4.51
2026-07-15	7,106,766	+18.9%	1,238,415	5.74
2026-06-30	5,979,529	-10.1%	1,392,913	4.29
2026-06-15	6,647,807	+3.0%	1,517,495	4.38
2026-05-29	6,457,486	-2.8%	1,681,733	3.84
2026-05-15	6,642,770	-5.6%	2,837,568	2.34
2026-04-30	7,033,879	-13.7%	2,424,367	2.90
2026-04-15	8,150,190	+4.5%	2,003,934	4.07
2026-03-31	7,795,289	+2.0%	1,679,789	4.64
2026-03-13	7,644,457	+7.4%	1,421,643	5.38
2026-02-27	7,115,529	-5.3%	1,593,259	4.47
2026-02-13	7,511,701	+2.7%	2,623,697	2.86
2026-01-30	7,312,662	-0.3%	1,400,927	5.22
2026-01-15	7,337,195	-2.5%	1,574,238	4.66
2025-12-31	7,522,583	-26.1%	1,444,715	5.21
2025-12-15	10,184,962	+11.4%	1,283,095	7.94
2025-11-28	9,146,282	+1.0%	1,344,797	6.80
2025-11-14	9,057,721	+3.9%	2,242,340	4.04
2025-10-31	8,715,642	+16.9%	1,471,923	5.92
2025-10-15	7,455,566	-5.0%	1,535,678	4.85

Daily short volume

FINRA Reg SHO, the last 30 sessions. JSON

As of 12 October 2026, the short share of MPLX volume is 61.2%, down 3.4 points over the last five sessions. Over the last 30 readings it ranged from 47.3% (30 September 2026) to 80.7% (18 September 2026). The latest reading is in line with the 30-session average of 60.2%, on 355K shares reported.

Date	Short volume	Total volume	Short share	Exempt
2026-10-12	217K	355K	61.2%	0
2026-10-09	488K	724K	67.3%	1,227
2026-10-08	236K	361K	65.4%	3
2026-10-07	327K	526K	62.1%	0
2026-10-06	201K	362K	55.6%	0
2026-10-05	247K	382K	64.7%	0
2026-10-02	287K	459K	62.4%	230
2026-10-01	371K	736K	50.5%	0
2026-09-30	315K	667K	47.3%	9
2026-09-29	430K	707K	60.8%	34
2026-09-28	483K	759K	63.6%	1,190
2026-09-25	429K	827K	51.8%	400
2026-09-24	256K	475K	53.9%	11,324
2026-09-23	362K	605K	59.9%	1,899
2026-09-22	343K	552K	62.1%	15,243
2026-09-21	256K	485K	52.9%	200
2026-09-18	279K	346K	80.7%	801
2026-09-17	229K	371K	61.7%	0
2026-09-16	539K	848K	63.5%	0
2026-09-15	291K	509K	57.1%	0
2026-09-14	322K	670K	48.0%	200
2026-09-11	134K	229K	58.3%	1,104
2026-09-10	210K	401K	52.4%	313
2026-09-09	269K	439K	61.2%	0
2026-09-08	346K	618K	55.9%	0
2026-09-04	251K	383K	65.6%	6
2026-09-03	306K	477K	64.2%	0
2026-09-02	250K	438K	57.0%	3,341
2026-09-01	439K	555K	79.1%	0
2026-08-31	214K	365K	58.6%	0

Fails to deliver

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

As of 8 September 2026, the fails-to-deliver balance in MPLX is 1,469 shares, up 1,459 shares over the last settlement date. Over the last 30 readings it ranged from 1 share (21 August 2026) to 366,779 shares (18 May 2026). The latest reading sits at the bottom of that range.

Settlement	Shares failed	Price	Value
2026-09-08	1,469	$59.67	$88K
2026-09-04	10	$59.34	$593
2026-08-28	2	$59.51	$119
2026-08-26	3,491	$58.36	$204K
2026-08-21	1	$58.60	$59
2026-08-20	1,235	$58.69	$72K
2026-08-11	1,556	$58.70	$91K
2026-08-07	98,448	$60.42	$5.9M
2026-08-05	353	$60.51	$21K
2026-08-04	7,389	$58.91	$435K
2026-08-03	2,457	$58.45	$144K
2026-07-30	4	$57.79	$231
2026-07-20	807	$57.06	$46K
2026-07-14	445	$57.21	$25K
2026-07-08	109	$57.51	$6K
2026-06-22	3,888	$56.84	$221K
2026-06-17	505	$56.08	$28K
2026-06-16	505	$55.67	$28K
2026-06-15	12,962	$56.87	$737K
2026-06-03	35,227	$55.68	$2.0M
2026-06-02	35,226	$54.99	$1.9M
2026-06-01	35,226	$54.65	$1.9M
2026-05-22	45,212	$55.62	$2.5M
2026-05-19	43,700	$55.44	$2.4M
2026-05-18	366,779	$54.77	$20.1M
2026-05-08	400	$56.27	$23K
2026-05-06	23,892	$55.66	$1.3M
2026-04-20	1,169	$55.88	$65K
2026-04-15	14	$55.01	$770
2026-04-09	744	$55.89	$42K

Insider trades

SEC Form 4, newest first, 50 of 100 shown. JSON

No open-market insider trades were reported for MPLX in the last 90 days. The most recent filings are listed below. Latest filing: Peiffer Garry L. (Director) on 2026-08-14.

Date	Insider	Title	Type	Shares	Price	Value	Owned after
2026-08-14	Peiffer Garry L.	Director	Grant	1K	$0.00	$0	69K
2026-08-14	Walker Ray N JR	Director	Grant	82	$0.00	$0	5K
2026-08-14	HELMS CHRISTOPHER A	Director	Grant	1K	$0.00	$0	86K
2026-08-14	SURMA JOHN P	Director	Grant	2K	$0.00	$0	95K
2026-08-14	STICE J MICHAEL	Director	Grant	983	$0.00	$0	58K
2026-08-14	SEMPLE FRANK M	Director	Grant	1K	$0.00	$0	63K
2026-08-14	Breves Christine S	Director	Grant	219	$0.00	$0	15K
2026-05-15	Breves Christine S	Director	Grant	277	$0.00	$0	14K
2026-05-15	HELMS CHRISTOPHER A	Director	Grant	1K	$0.00	$0	84K
2026-05-15	Peiffer Garry L.	Director	Grant	1K	$0.00	$0	68K
2026-05-15	SEMPLE FRANK M	Director	Grant	1K	$0.00	$0	62K
2026-05-15	STICE J MICHAEL	Director	Grant	1K	$0.00	$0	57K
2026-05-15	SURMA JOHN P	Director	Grant	2K	$0.00	$0	93K
2026-05-15	Walker Ray N JR	Director	Grant	78	$0.00	$0	4K
2026-05-15	Walker Ray N JR	Director	Grant	78	$0.00	$0	4K
2026-05-15	SURMA JOHN P	Director	Grant	2K	$0.00	$0	93K
2026-05-15	STICE J MICHAEL	Director	Grant	1K	$0.00	$0	57K
2026-05-15	SEMPLE FRANK M	Director	Grant	1K	$0.00	$0	62K
2026-05-15	Peiffer Garry L.	Director	Grant	1K	$0.00	$0	68K
2026-05-15	HELMS CHRISTOPHER A	Director	Grant	1K	$0.00	$0	84K
2026-05-15	Breves Christine S	Director	Grant	277	$0.00	$0	14K
2026-04-30	Breves Christine S	Director	Grant	2K	$0.00	$0	14K
2026-04-30	HELMS CHRISTOPHER A	Director	Grant	2K	$0.00	$0	83K
2026-04-30	Peiffer Garry L.	Director	Grant	2K	$0.00	$0	66K
2026-04-30	SEMPLE FRANK M	Director	Grant	3K	$0.00	$0	61K
2026-04-30	STICE J MICHAEL	Director	Grant	3K	$0.00	$0	56K
2026-04-30	SURMA JOHN P	Director	Grant	3K	$0.00	$0	92K
2026-04-30	Walker Ray N JR	Director	Grant	2K	$0.00	$0	4K
2026-04-30	Walker Ray N JR	Director	Grant	2K	$0.00	$0	4K
2026-04-30	SURMA JOHN P	Director	Grant	3K	$0.00	$0	92K
2026-04-30	STICE J MICHAEL	Director	Grant	3K	$0.00	$0	56K
2026-04-30	SEMPLE FRANK M	Director	Grant	3K	$0.00	$0	61K
2026-04-30	Peiffer Garry L.	Director	Grant	2K	$0.00	$0	66K
2026-04-30	HELMS CHRISTOPHER A	Director	Grant	2K	$0.00	$0	83K
2026-04-30	Breves Christine S	Director	Grant	2K	$0.00	$0	14K
2026-03-02	Mannen Maryann T.	Chairman, President & CEO	Tax withholding	6K	$59.22	$380K	165K
2026-03-02	Mannen Maryann T.	Chairman, President & CEO	Tax withholding	3K	$59.22	$202K	172K
2026-03-02	Mannen Maryann T.	Chairman, President & CEO	Tax withholding	3K	$59.22	$202K	175K
2026-03-02	Lyon Shawn M	Senior VP, Log. & Storage	Tax withholding	798	$59.22	$47K	28K
2026-03-02	Lyon Shawn M	Senior VP, Log. & Storage	Tax withholding	1K	$59.22	$61K	29K
2026-03-02	Lyon Shawn M	Senior VP, Log. & Storage	Tax withholding	920	$59.22	$54K	30K
2026-03-02	HAGEDORN CARL KRISTOPHER	Exec VP & Chief Fin Ofc	Tax withholding	663	$59.22	$39K	20K
2026-03-02	HAGEDORN CARL KRISTOPHER	Exec VP & Chief Fin Ofc	Tax withholding	916	$59.22	$54K	21K
2026-03-02	HAGEDORN CARL KRISTOPHER	Exec VP & Chief Fin Ofc	Tax withholding	422	$59.22	$25K	22K
2026-03-02	Floerke Gregory Scott	Exec. VP and COO	Tax withholding	797	$59.22	$47K	95K
2026-03-02	Floerke Gregory Scott	Exec. VP and COO	Tax withholding	1K	$59.22	$65K	96K
2026-03-02	Floerke Gregory Scott	Exec. VP and COO	Tax withholding	995	$59.22	$59K	97K
2026-03-02	Benson Molly R	Chief Legal Ofc & Corp Sec	Tax withholding	998	$59.22	$59K	46K
2026-03-02	Benson Molly R	Chief Legal Ofc & Corp Sec	Tax withholding	1K	$59.22	$73K	47K
2026-03-02	Benson Molly R	Chief Legal Ofc & Corp Sec	Tax withholding	614	$59.22	$36K	48K

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.

13F holders

Tracked managers holding MPLX at their latest 13F. JSON

2 of the 30 tracked managers held MPLX at their latest 13F, $40.1M in total at quarter-end prices. Appaloosa LP is the largest at $28.3M (0.4% of its portfolio) as of 2026-06-30. Over the prior quarter 1 added shares and 0 cut.

Fund	Quarter	Shares	Value	Of portfolio	Change in shares
Appaloosa LP	2026-06-30	502K	$28.3M	0.37%	0
Citadel Advisors	2026-06-30	209K	$11.8M	0.00%	+204K

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.

Financials

SEC XBRL, as filed. JSON

In Q2 FY 2026 (quarter ended 2026-06-30) Mplx reported revenue of $2.62B, up 11.0% from the same quarter a year earlier. In FY 2025 it generated $5.91B of operating cash flow and spent $400.0M on buybacks.

Cash: $1.03B
Total assets: $42.97B
Shares outstanding: 1,013,858,251

Quarterly, last 8 quarters

Quarter	Period end	Revenue	Net income	Margin	Diluted EPS
Q2 FY 2026	2026-06-30	$2.62B	n/a	n/a	n/a
Q1 FY 2026	2026-03-31	$2.35B	n/a	n/a	n/a
Q4 FY 2025derived	2025-12-31	$2.45B	n/a	n/a	n/a
Q3 FY 2025	2025-09-30	$2.46B	n/a	n/a	n/a
Q2 FY 2025	2025-06-30	$2.36B	n/a	n/a	n/a
Q1 FY 2025	2025-03-31	$2.46B	n/a	n/a	n/a
Q4 FY 2024derived	2024-12-31	$2.42B	n/a	n/a	n/a
Q3 FY 2024	2024-09-30	$2.35B	n/a	n/a	n/a

Fiscal years, with buybacks and dividends

Fiscal year	Ends	Revenue	Net income	Operating cash flow	Capex	Buybacks	Dividends
FY 2025	2025-12-31	$9.73B	n/a	$5.91B	$1.81B	$400.0M	n/a
FY 2024	2024-12-31	$9.19B	n/a	$5.95B	$1.06B	$326.0M	n/a
FY 2023	2023-12-31	$8.73B	$3.93B	$5.40B	$937.0M	$0	n/a
FY 2022	2022-12-31	$8.92B	$3.94B	$5.02B	$806.0M	$491.0M	n/a
FY 2021	2021-12-31	$8.02B	$3.08B	$4.91B	$529.0M	$630.0M	n/a

Quarters are the three-month figures the company reports; a fourth quarter marked derived is the fiscal year less the three reported quarters, since companies report it only inside the 10-K. Fiscal years are the annual figures. Buybacks are the cash the company paid to repurchase its common stock in the year, not the amount authorized. Balance sheet lines are as of 2026-06-30; shares outstanding as of 2026-07-30 from the cover page.

What this page is

Mplx 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 Mplx (MPLX), SEC CIK 1552000, listed on NYSE, classified by the SEC as pipe lines (no natural gas). 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 2026-09-30.JSON and CSV
Daily short volume: FINRA Reg SHO daily filesSource: FINRA.Every trading day, the morning after FINRA posts it. Latest 2026-10-12.JSON and CSV
Fails to deliver: SEC fails-to-deliver dataSource: SEC.Twice a month, a few weeks after the half month ends. Latest 2026-09-08.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
Financials: SEC EDGAR 10-K and 10-Q filingsSource: SEC.Weekly; values are as filed in the 10-Q and 10-K. 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 2026-08-04.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 2026-08-14.JSON and CSV
Company record: EDGAR filing index for CIK 1552000Ticker, 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 pipe lines (no natural gas)

Other company pages

Datasets

Frequently Asked Questions

How much of MPLX is sold short?

6,685,785 shares were held short at the 2026-09-30 settlement, 4.2 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 MPLX's daily short volume?

On 2026-10-12, 217,225 of the 354,755 MPLX shares reported to FINRA were sold short, 61.2% of the day's reported volume. Short volume is a flow for one day, not a position.

Does MPLX have fails to deliver?

The SEC's latest file shows 1,469 MPLX shares failed to deliver at settlement 2026-09-08. Fails are reported per settlement date and published twice a month with a lag.

Are MPLX insiders buying or selling?

No open-market insider trades were reported for MPLX in the last 90 days. The most recent filings are listed below. Latest filing: Peiffer Garry L. (Director) on 2026-08-14.

What did MPLX report last quarter?

Which tracked 13F managers own MPLX?

2 of the 30 tracked 13F managers held MPLX shares at their latest filing, $40.1M in all. The largest: David Tepper's Appaloosa LP (502K shares, $28.3M), Ken Griffin's Citadel Advisors (209K shares, $11.8M).

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