GetCoattail Research — AT&T is the carrier whose shares fell roughly a tenth in a day after SpaceX agreed to buy the low-band spectrum that could make Starlink Mobile a national rival, days after AT&T itself announced a fiber venture aimed at more than 60 million locations. The filings describe a register that narrowed at the top and concentrated underneath: three tracked superinvestors hold it, one of them is 98.8% of the cohort and raised its stake 29.2% in a quarter when the price fell 28.6%, the full market lost 247 filers while adding 15.68% more shares, insiders have recorded no purchase and exactly one sale in the entire parsed record, and short interest is up 43.4% in a year.
Start with the narrative. On October 8, 2026, SpaceX announced an agreement to buy Grain Management's nationwide 800 MHz spectrum portfolio — up to 14 megahertz of paired low-band airwaves, the kind that reach inside buildings — in a deal that still needs FCC approval and that the Wall Street Journal priced at about $8 billion in cash, as reported by multiple outlets. The market's answer came the next day: AT&T fell about a tenth on October 9 — one count put the close at $22.17, down 9.8%, on 140.3 million shares, about 182% above its three-month average volume. The same week brought AT&T's own expansion news: on October 6 it agreed to form a wholesale fiber venture with Global Infrastructure Partners and CPP Investments, keeping a 50% stake, targeting more than 60 million fiber locations by the end of 2030 from a start of nearly 5 million locations and more than 1 million subscribers, with closing expected in the first half of 2027. Underneath both stories sits a solid reported quarter: on July 22, AT&T posted second-quarter revenue of $31.6 billion, up 2.3%, adjusted earnings of $0.65 a share against $0.54 a year earlier, and adjusted EBITDA of $12.3 billion, up 5.2%, while reiterating guidance and accelerating planned 2026 buybacks to about $10 billion. Analysts sat above the price: a Yahoo Finance count on October 1 put the consensus at Moderate Buy across 29 analysts with an average target of $29.12 — 19.8% above the $24.30 close of October 2 on our price file, which ends that day, down 16.5% from its 252-session closing high of $29.10 set on March 27, 2026, and up 18.7% from its closing low of $20.48 set on July 1. The next scheduled test is the third-quarter report on October 21.
Now the filings. For AT&T — the fifty-third Filing Tape audit — the tape shows a tracked cohort that bought a falling quarter almost through a single name, a broad register that shed filers while its share count grew, an insider record with no purchase and a single sale in its entire parsed history, and a borrow that has rebuilt by more than two-fifths in a year.
Lens 1: the superinvestors — three holders, one of them 98.8%, and a 28.8% add into a 28.6% fall
We track 83 large, mostly long-only managers whose 13F portfolios we collect directly from SEC EDGAR. As of June 30, 2026, 3 held AT&T long — no option rows — totalling 1,947,125 shares worth $40,305,488. The direction count, on the collection's own labels, is no new positions, one increase, one decrease and one unchanged, and the collection's exit list holds no AT&T row at all. The cohort total moved from 1,511,928 shares at March 31, across three filing rows, to 1,947,125 at June 30, a change of +28.78%, a difference of +435,197 shares.
Almost all of that register is one name. John Rogers - Ariel Investments holds 1,924,404 shares worth $39,835,163, a 0.4% portfolio weight, flagged increased by 29.2% — 98.8% of the tracked cohort's AT&T shares. The other two holders are rounding errors by comparison: Arnold Van Den Berg - Century Management holds 11,394 shares worth $235,856, a 0.05% weight, flagged decreased by 0.5%, and Mairs & Power Funds holds 11,327 shares worth $234,469, a 0.0% weight, flagged unchanged. Per-holder quarter changes matched by filing continuity agree with the collection's own percentage labels for all three continuing holders — there is no label mismatch in this register. The cohort's implied price, $20.70 per share, sits exactly on the June 30 close of $20.70. The price fell from $28.99 at March 31 to $20.70 at June 30, a change of -28.6% — this register added 28.78% more shares into that fall, and one holder did effectively all of the adding.
Lens 2: institutions — 247 fewer filers, 615 million more shares
Zoom out to the whole 13F market and the register narrows while it grows. At June 30, 2026, 2,673 institutions reported positions, down 247 from 2,920 at March 31 (-8.46%), and 2,663 of them reported long positions. Reported shares rose 15.68%, from 3,925,836,616 to 4,541,280,466 shares — 615,443,850 more shares than the prior quarter, spread across fewer filers. Reported aggregate value fell 17.51% to $94,023,811,832; the aggregate includes option rows, so we headline filer and share counts and label dollars "reported" (see methodology). Here the implied value per share, $20.70, sits exactly on the June 30 close of $20.70 — no gap at all — and we still headline the share count, because the dollar total moves with the price as well as with positioning: shares rose 15.68% in a quarter when the price fell 28.6%, and the reported value fell anyway. The two 13F lenses point the same way, at very different scales: the tracked cohort added 28.78% with one holder doing the adding, and the broad market added 15.68% more shares while 247 filers left the register.
Lens 3: the 5% register — two filings in the parsed set, both of them Vanguard paper
Our full parse holds just two SC 13D/G filings for AT&T — one SC 13G filing and one SC 13G/A amendment, and no SC 13D of any kind in the parsed set, two reporting-person rows across two names, the most recent filed April 29, 2026. Both rows are the hand-off pattern this series keeps meeting. In an SC 13G/A filed March 26, 2026, The Vanguard Group prints 0 shares (0.0%) as of March 13, 2026. In an SC 13G filed April 29, 2026, Vanguard Capital Management prints 526,107,236 shares (7.53%) as of March 31, 2026 — the register's largest and most recent row. That is the whole 5% register in our parsed coverage: two filings, two Vanguard names, one moving to zero and the other appearing at 7.53%, and no activist paper at all. Read as filed — and the rows are reported here exactly as filed, never summed — the register describes a passive complex re-papering its stake under a different entity name, on a name where the 13F lenses count thousands of filers but the 5% tape, in this coverage, holds only this one complex.
Lens 4: insiders — no purchase, and exactly one sale, in the entire parsed record
The parsed Form 4 record holds 316 filings through October 2, 2026. Across the whole record, open-market purchases total exactly 0 transactions — no shares, no dollars, no buyers, and none of them recorded as an officer purchase, because there are none to record. Against that stands exactly 1 sale in the entire parsed record, totalling 1,500 shares and $41,347.50, by one seller, recorded as an officer sale. The recent windows are emptier still: the last year holds 163 filings and no purchase or sale transactions at all, and the last 90 days hold 23 filings and likewise no purchases and no sales — filings keep arriving, but none of them is an open-market trade in either direction. Our site's insider aggregate, compiled as of October 12 over its 90-day window, carries no AT&T row at all; we report that absence as printed rather than merging the two collections, and note only that a window with no transactions in the full parse has nothing for a 90-day trade aggregate to carry. We assign no motives to any of it; a tape with zero purchases and one sale in the parsed record is the fact.
Lens 5: Congress — three members, five purchases against three sales, both parties
Across the congressional record we maintain, AT&T does appear — modestly, and on both sides of the aisle. The combined record (as of October 3, 2026) carries 3 members, 5 purchase transactions and 3 sale transactions, with the most recent purchase dated June 29, 2026, and both parties represented. The House aggregate (as of October 3, 2026) carries 2 members, 4 purchases and 3 sales, the most recent purchase on June 5, 2026, all Republican; the Senate aggregate (as of October 1, 2026) carries 1 member, 1 purchase and no sales, the most recent purchase on June 29, 2026, a Democrat. The two chamber aggregates sum exactly to the combined row. In a series where this lens is often blank, AT&T's congressional tape is small but two-sided — single-digit counts that we report without inflating them into a signal.
Lens 6: short interest — 130,448,062 shares, up 43.4% in a year
FINRA's files carry the borrow across 137 settlements, from January 15, 2021. As of September 15, 2026 — the most recent settlement — 130,448,062 AT&T shares were sold short, with days-to-cover of 3.52. The latest step was up: the reading rose 4.14% from the prior settlement's 125,256,838 shares on August 31, 2026. The level sits near the top of the series without reaching it: the peak is 143,378,919 shares on September 13, 2024, a fact we verified by taking the maximum across the whole series, and the latest reading sits 9.0% below it. Against September 15, 2025 the latest reading is up 43.4% from 90,962,568 shares — the borrow has rebuilt by more than two-fifths in a year. Against the fundamentals file's 6,852,385,650 shares outstanding, that is 1.90% of the share count. The June 30, 2026 settlement — the date the 13F lenses snapshot — printed 125,702,888 shares, below the present. The recent settlements run 107,643,650 on July 15, then 130,021,999, 117,455,463, 125,256,838 and 130,448,062. The series minimum is 73,266,608 shares on March 15, 2022; the first settlement in the series, on January 15, 2021, printed 133,167,972 shares — slightly above today's reading.
The borrow spent a year rebuilding and sits within a tenth of its series peak, before the October spectrum selloff that the settlement calendar has not yet printed. Set beside the ownership lenses, that leaves a register where the long side concentrated through a falling second quarter while the short side quietly grew back.
The gap, stated plainly
The narrative describes a carrier that grew second-quarter revenue 2.3% to $31.6 billion with adjusted earnings up from $0.54 to $0.65, that is building a fiber venture aimed at more than 60 million locations, that carries a Moderate Buy consensus and a $29.12 average target against a $24.30 October 2 close — and that then lost about a tenth of its value in a day when a satellite rival bought the low-band spectrum to compete for its customers, a threat no filing in this audit can price. The tracked superinvestors held 1,947,125 shares at June 30 across three holders, having added 28.78% in a quarter when the price fell 28.6%, with one increase, one decrease, one unchanged and no exit, and with Ariel at 98.8% of the cohort after raising its own stake 29.2%. The full market moved the same way, larger and narrower: 4,541,280,466 reported shares, up 615,443,850, across 2,673 filers — 247 fewer than the prior quarter. The 5% register printed two filings, both Vanguard paper: one entity at zero, another at 7.53%. Insiders, across 316 parsed filings, recorded zero purchases against exactly one sale totalling $41,347.50, and no trades at all in the last year. Congress registers three members, five purchases and three sales. And the borrow, after a year of rebuilding, stands at 130,448,062 shares — up 43.4% year over year, 9.0% below its September 13, 2024 peak. One plausible reading is that the registers are describing different AT&T stories on different clocks: the broad long register used a falling second quarter to concentrate — fewer filers, more shares — the tracked cohort's add was really a single manager's add, the insider tape kept a no-trade shape it has barely ever broken in the parsed record, members of Congress bought modestly on both sides of the aisle, and short sellers spent a year rebuilding a borrow that the October 9 drop will only enter in settlements published later this month. The record supports each clause separately; it does not say which register is right, and it cannot — the tracked cohort's whole position is a June 30 snapshot of 1,947,125 shares, taken before both the fiber venture and the spectrum deal existed as news.
What would change the picture
Nothing above is a recommendation. It is a record. These are the filings that would change the description:
- 1. The 2026Q3 13Fs (filing window closing mid-November 2026). The tracked cohort held 1,947,125 shares at June 30 across three holders, after a +28.78% move driven by one increase. Whether Ariel's 1,924,404 shares — 98.8% of the cohort — grow again, hold, or reverse is the first thing the next register will answer: an Ariel exit would erase the cohort almost entirely at a stroke, and a second holder adding in size would make this register something other than a single-name position.
- 2. A first insider purchase — or a second sale. The parsed record holds exactly 0 purchase transactions and exactly 1 sale across 316 filings, and none of either kind in the last year. Any open-market purchase would be the first of its kind in the parsed record, and any sale would double the record's entire sale count.
- 3. An original SC 13D, or a non-Vanguard 13G. The 5% register in our parsed coverage holds two filings, both Vanguard entities. A first 13D in the parsed set — any filer declaring an active stake — or a 13G from outside the index complex would change this lens from re-papered passive holdings into something else.
- 4. Whether the borrow passes its peak. Short interest stands at 130,448,062 shares, up 43.4% in a year and 9.0% below the September 13, 2024 peak of 143,378,919, after a 4.14% uptick in the latest settlement. The settlements that will print the October 9 selloff have not been published yet: a reading above the 2024 peak would mark a borrow larger than any in the series, and a sharp fall would show the shorts covering into the drop instead.
- 5. Whether the filer count keeps shrinking while shares keep rising. The broad register lost 247 filers in the second quarter while adding 615,443,850 reported shares, and the tracked cohort added 435,197 shares. A second straight quarter of that pairing would deepen the concentration this audit describes; a broadening register would unwind it.
Until one of those prints, the record describes a stock held by three of our 83 tracked superinvestors — 1,947,125 shares, up 28.78% in the quarter its price fell 28.6%, with one holder at 98.8% — whose full market lost 247 filers while adding 615,443,850 reported shares in the same quarter, whose 5% register in our coverage is two Vanguard filings, whose insiders have recorded no purchases and exactly one sale in the entire parsed record, whose congressional register holds three members with five purchases against three sales, and whose borrow is up 43.4% in a year — all of it snapshot at June 30, in a quarter the long registers spent concentrating and the price spent falling.
Related reading: Two of 83: Both Superinvestors Trimmed Champion Homes as the Price Rose 18.5%. Its Insiders Have Never Bought a Share. — Filing Tape #52; Seven of 83: Five Superinvestors Raised Medtronic as Its Price Fell 9.7%. Short Interest Then Jumped 42% in One Settlement. — Filing Tape #51; Zero of 83: The Superinvestors Aren't in IREN — Filing Tape #1. AT&T's own page: AT&T Inc. (T) on GetCoattail.
Methodology and data notes
- Superinvestor lens: 83 managers collected directly from SEC EDGAR Form 13F (managers_13f collection), positions as of June 30, 2026; AT&T identified by CUSIP 00206R102. Three distinct managers hold long positions totalling 1,947,125 shares; all three reported rows are long (no put or call rows); the direction count on the collection's labels is no new, one increased, one decreased and one unchanged, and the collection's exit list contains no AT&T row. Quarter-to-quarter cohort totals (1,511,928 shares at March 31 across three filing rows; 1,947,125 shares at June 30 across three filing rows; change +28.78%) are from the site pipeline's holdings files on the same CUSIP basis in both quarters, and the pipeline's second-quarter share and value totals match the EDGAR collection's long totals exactly (differences of 0 shares and $0). Per-holder quarter changes are matched by filing continuity across the two pipeline files and agree with the EDGAR collection's own percentage labels for all three continuing holders. Ariel's share of the cohort is 98.8% = 1,924,404 / 1,947,125.
- Full-market lens: SEC Form 13F Data Sets full-market aggregation. The primary table is the full13f collection's by-ticker file (holders = distinct filers reporting the CUSIP; 2,663 reported long positions out of 2,673 filers). AT&T reports under the single CUSIP 00206R102, and the backfill fixtures' by-CUSIP row for that CUSIP matches the by-ticker row exactly (2,673 filers; 4,541,280,466 shares; $94,023,811,832 reported; 2,920 prior filers; $113,985,819,733 prior reported value). The by-ticker file's entered/exited fields (1,747 and 1,994, a net of -247 that matches the change in holder count) are gross flows, so this audit headlines the net change. Reported-value caution: the aggregate value ($94,023,811,832 over 4,541,280,466 shares) implies $20.70 per share against a June 30, 2026 close of $20.70 in our price file, a gap of 0.0% — exact agreement this quarter, reported here as printed. The aggregate sums the VALUE of every information-table row — including put and call option rows — while the share count covers long common-stock rows only, so we headline filer and share counts and label dollar values "reported."
- Insider lens: full-parse Form 4 aggregation (agg_by_ticker), record as of October 2, 2026 (316 filings). Sale and purchase counts are transaction-code counts (S and P) in non-derivative rows; grants and exercises are not counted as purchases, and one filing can contain many transaction rows. Purchase transactions total exactly 0 across the parsed record (0 shares, $0.00, zero buyers, none of them officer purchases) — and zero in both the 90-day window and the last year. Sale transactions total exactly 1 across the record (1,500 shares, $41,347.50, one seller, recorded as an officer sale); the 90-day window (23 filings) and the last year (163 filings) each hold none. The site's insider aggregate (compiled as of October 12, 2026, 90-day window) carries no AT&T row, and this audit reports that absence exactly as printed, without merging the two collections. "Purchases" in this audit is scoped to this parsed record, whose 316 filings are the coverage stated here.
- 13D/G lens: full-parse SC 13D/G parsed filings (2 filings matching issuer CIK 732717 on CUSIP 00206R102, 2 reporting-person rows across 2 names: one SC 13G filing and one SC 13G/A amendment, no SC 13D filings), filings through April 29, 2026. The site aggregation's by-ticker file carries the same totals (2 filings, 2 reporters, latest filing April 29, 2026, maximum 7.53%, total reported 526,107,236 shares), so the aggregate and the parse agree here. The Vanguard Group's row (0 shares at 0.0% as of March 13, 2026, filed March 26, 2026) and Vanguard Capital Management's row (526,107,236 shares at 7.53% as of March 31, 2026, filed April 29, 2026) are reported as filed, under the reporting-person names exactly as they appear. No rows are summed in the article, because aggregation totals across these rows would add different dates together. No reason for any change is asserted — the filings themselves are the record. The parsed coverage for this issuer holds these two filings; a 5% holder that has not filed in the covered window would not appear here.
- Congress lens: Senate PTR archive and House PTR archive as maintained on this site. The combined record (as of October 3, 2026) carries 3 members, 5 purchase transactions and 3 sale transactions, most recent purchase June 29, 2026, both parties; the House aggregate (as of October 3, 2026) carries 2 members, 4 purchases and 3 sales, most recent purchase June 5, 2026; and the Senate aggregate (as of October 1, 2026) carries 1 member, 1 purchase and no sales, most recent purchase June 29, 2026. The chamber figures sum exactly to the combined row.
- Short interest lens: FINRA Equity Short Interest files (biweekly settlement dates), collected directly from FINRA's public distribution. The published series covers 137 settlements from January 15, 2021 (133,167,972 shares) to September 15, 2026. The latest reading is 130,448,062 shares on September 15, 2026, which sits 9.0% below the series maximum of 143,378,919 shares on September 13, 2024 (verified by a maximum query over the series, not read off the latest row), up 43.4% from the September 15, 2025 reading of 90,962,568 and up 4.14% from the prior settlement (125,256,838 on August 31, 2026). The series minimum is 73,266,608 shares on March 15, 2022. FINRA publishes each settlement about two weeks after the fact, so the October 9, 2026 price drop is not yet in this series. The share-count ratio (1.90%) uses the fundamentals file's shares-outstanding figure below.
- Fundamentals note: our fundamentals collection carries AT&T's revenue of $125,648,000,000 labelled fiscal 2025, its net income of $21,953,000,000 labelled fiscal 2025, and its assets of $420,198,000,000 labelled fiscal 2025. The file is marked ok for this name, with no missing fields: shares outstanding of 6,852,385,650 (as of July 16, 2026, sourced in the file to a dei EntityCommonStockSharesOutstanding count) and a file-computed market value of $167,403,783,520.68. The file's price for the name is $24.43 as of October 6, 2026; our daily-close file ends October 2, 2026 at $24.30, and we keep the two files' figures separate rather than blending them.
- Prices: our own daily-close file for AT&T through October 2, 2026 ($24.30 close, -2.2% year to date on that file; 252-session closing high $29.10 on March 27, 2026; 252-session closing low $20.48 on July 1, 2026; closes of $28.99 at March 31, 2026 and $20.70 at June 30, 2026, a second-quarter change of -28.6%; change from June 30 to October 2 of +17.4% ((24.30 / 20.70) − 1)). The drawdown from the 252-session closing high is -16.5%, the gain from the 252-session closing low is +18.7%, and the series in our price file begins June 1, 2021. The October 9, 2026 decline is outside this file and is cited from press reports only, as stated in the text.
- Market context sources: Seeking Alpha / TradingView weekly trending summary, October 11, 2026 (SpaceX spectrum deal; AT&T down almost 11% on Friday, October 9 — checked October 12, 2026); the SpaceX–Grain Management agreement (announced October 8, 2026; nationwide 800 MHz portfolio, up to 14 megahertz of paired spectrum; FCC approval required; about $8 billion in cash as reported from the Wall Street Journal by multiple outlets, October 2026); the October 9 session detail (close $22.17, down 9.8%, volume 140.3 million shares, about 182% above the three-month average — MEXC market summary, October 2026); the company's second-quarter results (released July 22, 2026; revenue $31.6 billion, up 2.3%; adjusted earnings $0.65 a share; adjusted EBITDA $12.3 billion, up 5.2%; full-year guidance reiterated; 2026 buybacks accelerated to about $10 billion — company release as reported by multiple outlets); the fiber venture agreement (announced October 6, 2026; AT&T to retain 50%; more than 60 million fiber locations targeted by end of 2030; nearly 5 million starting locations and more than 1 million subscribers; closing expected first half of 2027 — company announcement as reported in October 2026 coverage); the consensus detail (Moderate Buy across 29 analysts; average target $29.12 — Yahoo Finance data as reported October 1, 2026); the third-quarter report date (October 21, 2026 — company calendar as reported October 2026). Figures we could not confirm against two sources were left out.
- AT&T is in the GetCoattail stock-page universe: AT&T Inc. (T) stock page. Series data: t_lens_data.csv · t_short_interest_series.csv. Earlier audits: Champion Homes · Medtronic · IREN.
Past patterns are not a promise of future results. For education only — not investment advice.
This article describes public filings as of the dates stated. It is not investment advice and makes no recommendation. Filings lag reality: 13F positions are as of June 30, 2026, and later trading is not yet public.
Revision history
- v1.0 — October 12, 2026: first publication.