Anthropic's $120.5B SpaceX Compute Deal: What the 90-Day Exit Clause Means After the 'Mid-2027' Report

🤝 On Wednesday, November 11, a set of secondhand meeting notes put a date on a question SpaceX shareholders had been circling for weeks: how long will Anthropic keep renting SpaceX's AI compute? The notes, posted on X by the account @jukan05, said Anthropic told sell-side analysts that "the contract with SpaceX will not be" extended beyond the middle of next year. Within hours, Elon Musk answered a reply thread about it: "We would be happy to take the compute back. No problem. But I think the opposite is going to happen."

Neither Anthropic nor SpaceX has confirmed the analyst-meeting remark. The contract terms it refers to are not rumor. They sit in Anthropic's amended IPO registration statement, filed with the SEC on November 10, 2026, and in SpaceX's third-quarter 10-Q.

What the filings actually say

Anthropic's S-1/A (Amendment No. 2, filed November 10, 2026) describes agreements with SpaceX.AI LLC — "formerly known as X.AI LLC," a wholly owned subsidiary of Space Exploration Technologies Corp. — signed and amended between May and October 2026 to access compute powered by NVIDIA GPUs.

"Under the SpaceXAI Arrangements, we agreed to spend an aggregate of up to $120.5 billion over terms extending into 2029, consisting of approximately $3.1 billion in the aggregate per month once all capacity has been delivered, which we expect in December 2026, with different fees during capacity ramping periods. Following initial non-cancelable periods ending in January 2027 and March 2027 under the respective agreements, each agreement may be cancelled by either party upon 90 days' advance written notice."

1. "Up to." The $120.5 billion is a ceiling into 2029, not a guaranteed backlog.

2. The run-rate depends on delivery. About $3.1 billion a month applies once all capacity is delivered, which Anthropic expects in December 2026. Fees differ during the ramp.

3. The exit is two-sided. After January 2027 and March 2027, either party can cancel on 90 days' written notice.

DataCenterDynamics, reading the S-1 update, reports about $895.4 billion of aggregate purchase and lease commitments, including $121.3 billion with Google, $120.5 billion with SpaceX, $110 billion with Amazon, and $44.9 billion with Microsoft. In that reading, the Google, Amazon, and Microsoft deals are mostly non-cancelable, while the SpaceX deal is cancelable on 90 days' notice.

The SpaceX side of the ledger

SpaceX's 10-Q for the quarter ended September 30, 2026, filed October 22, does not name Anthropic. It does disclose a concentration investors have been tying to this contract. That table, including AI at 52% of Q3 2026 revenue, is discussed in the November 11 revenue note.

| SpaceX Q3 2026 (10-Q) | Figure |

| --- | --- |

| Total revenues, Q3 2026 | $14,575 million |

| SI segment revenue, Q3 2026 | $7,560 million (vs. $813 million in Q3 2025) |

| of which "SI Solutions & Infrastructure" | $7,022 million (vs. $359 million) |

| "Customer B" share of consolidated revenue, Q3 2026 | 34.5% |

| "Customer B" share, nine months 2026 | 24.2% |

The filing says revenue from Customer B "relates to the SI segment." Bloomberg reported, citing one person familiar with the matter, that Customer B is Anthropic. We have not opened the Bloomberg piece and rely on secondary write-ups (TeslaNorth, Tenbrief). Treat the identification as reported, not confirmed.

For scale only: 34.5% of $14,575 million is roughly $5.0 billion for the quarter. That is our arithmetic on the 10-Q's percentages, not a figure SpaceX disclosed in dollars. A fully delivered $3.1 billion monthly rate would be about $9.3 billion per quarter — again simple multiplication, and only valid if all capacity is delivered and nothing is renegotiated.

Why "mid-2027" is not a coincidence

Put the clause on a calendar. If notice were served the day each non-cancelable period ends, the agreements would wind down roughly 90 days later:

| Agreement set | Non-cancelable period ends | Earliest end if notice served then |

| --- | --- | --- |

| First | January 2027 | ~late April / early May 2027 |

| Second | March 2027 | ~late June 2027 |

The filing gives no exact days and does not say notice can be served early, so the dates are approximate. "Mid-2027" still lines up with the earliest point either side can walk away. Two readings are possible, and the evidence does not settle between them.

Reading A (intent): Anthropic signaled it plans to exercise its exit, perhaps because its own compute (Google TPUs, AWS, Microsoft/NVIDIA and an AMD Helios commitment also described in the S-1) will be online.

Reading B (contract description): Anthropic described what the contract permits, possibly in answer to a hypothetical. That is the interpretation X user @aaronburnett offered — the post Musk was replying to — calling it a "secondhand meeting note without context." The display name is unverified.

What is genuinely new on November 11 is a reported statement of intent. What is not new is the exit right; it was disclosed in the filing.

What Musk actually said — and didn't

Musk's reply (November 11, 2026, 17:40 UTC) is two sentences: "We would be happy to take the compute back. No problem. But I think the opposite is going to happen." It does not confirm the meeting remark, and it does not say notice has been received. "The opposite" is undefined. The natural reading is more compute, not less, and that is interpretation.

In a separate reply the same day (19:01 UTC), he wrote: "SpaceX has a chance of going about half the GW next year of actually usable compute." The sentence is ambiguous as posted (half of what total is not stated), so we do not convert it into a number. He added that it takes SpaceX "~2 months working 24/7 to get a large compute cluster working reliably," and guessed "closer to 6 months for others" — a claim about competitors we cannot verify.

The two-sided risk

The exit clause is often discussed as a downside for SpaceX. It is symmetric. On the November 7 episode of the All-In podcast, Chamath Palihapitiya argued that if data-center supply tightens, SpaceX could serve notice itself and re-price capacity at market rates (as quoted by TeslaNorth). That is an opinion, not a disclosed plan. The filings support only the narrow point: neither side is locked in after early 2027.

As reported by Benzinga in November 2026, citing Reuters on May 28, Musk described an initial 180-day lease, and SpaceX wanted flexibility to reclaim capacity if its own demand surged.

For SpaceX the practical questions become:

Re-deployment: If Anthropic leaves, can the GPUs be re-leased or absorbed by SpaceX's own Grok workloads without a revenue gap? Musk's reply implies yes; there is no disclosed backlog of replacement customers. See the separate note on Grok Build and SpaceXSI.

Concentration: One customer at 34.5% of quarterly revenue is a disclosed concentration risk regardless of who it is.

Pricing: The S-1 gives an aggregate monthly figure, not a per-GPU price, so outsiders cannot judge whether the contract is above or below market.

Verified vs. claimed vs. unknown

| Category | Item |

| --- | --- |

| Verified (filings) | Up to $120.5B through terms into 2029; ~$3.1B/month at full delivery (expected Dec 2026); non-cancelable periods end Jan and Mar 2027; then 90-day notice by either party (Anthropic S-1/A, Nov 10) |

| Verified (filings) | Customer B = 34.5% of SpaceX Q3 revenue, tied to the SI segment (SpaceX 10-Q, Oct 22) |

| Reported (DataCenterDynamics' reading of the S-1) | About $895.4B of purchase and lease commitments: $121.3B Google, $120.5B SpaceX, $110B Amazon, $44.9B Microsoft; Google, Amazon, and Microsoft mostly non-cancelable; SpaceX cancelable on 90 days' notice |

| Verified (public post) | Musk: "We would be happy to take the compute back. No problem. But I think the opposite is going to happen." (Nov 11) |

| Reported, unconfirmed | Anthropic told sell-side analysts it will not extend beyond mid-2027 (@jukan05 notes; no meeting host or speaker named) |

| Reported, unconfirmed | Customer B is Anthropic (Bloomberg, one source) |

| Unknown | Whether any notice has been served; replacement demand; contract pricing vs. market |

What to watch next

Anthropic's next S-1 amendment or prospectus: any change to the SpaceXAI paragraph would be the first primary-source update.

SpaceX's Q4 10-K: whether full capacity was delivered in December 2026, and whether Customer B's share changes.

Any 8-K from SpaceX describing a material contract change.

Direct statements from Anthropic or SpaceX executives, as opposed to secondhand notes.

Running public status is on the SpaceX tracker. How a SpaceX exposure is held is covered in How to invest in SpaceX. Other notes are indexed at SpaceX news. The $120.5 billion was a ceiling with an early-2027 exit for both sides, and the November 11 report is a secondhand claim about which side might use it.

FAQ

Q: How much is Anthropic's SpaceX compute deal worth?

A: Up to $120.5 billion through 2029, and about $3.1 billion a month after full delivery, expected in December 2026. A ceiling, not a guaranteed backlog.

Q: Can Anthropic cancel its SpaceX contract?

A: After non-cancelable periods ending in January 2027 and March 2027, either party can cancel on 90 days' written notice. DataCenterDynamics reads the SpaceX deal as cancelable on that notice, and the Google, Amazon, and Microsoft deals as mostly non-cancelable.

Q: Did Anthropic cancel the SpaceX compute contract?

A: No cancellation or notice has been reported. The mid-2027 remark is secondhand and unconfirmed, from @jukan05 notes that name no host or speaker. Musk's reply does not say notice was received.

Q: Is Anthropic SpaceX's Customer B?

A: Bloomberg reported that, citing one person. The 10-Q does not name Anthropic. Customer B was 34.5% of Q3 2026 revenue and 24.2% for nine months, tied to the SI segment. Reported, not confirmed in the filings.

Q: What did Elon Musk say about Anthropic leaving?

A: On November 11, 2026, at 17:40 UTC, he wrote: "We would be happy to take the compute back. No problem. But I think the opposite is going to happen." Benzinga, citing Reuters on May 28, reports an initial 180-day lease and a wish to reclaim capacity if SpaceX demand surged.

Sources

1. Anthropic, PBC — Form S-1/A (Amendment No. 2), filed November 10, 2026. SEC filing (retrieved Nov 12, 2026)

2. Space Exploration Technologies Corp. — Form 10-Q for the quarter ended September 30, 2026, filed October 22, 2026. SEC filing (retrieved Nov 12, 2026)

3. Elon Musk on X, November 11, 2026, 17:40 UTC. Post

4. Elon Musk on X, November 11, 2026, 19:01 UTC. Post

5. @jukan05 on X, November 11, 2026, 11:46 UTC (meeting notes). Post

6. X user @aaronburnett on X, November 11, 2026. Post

7. TeslaNorth, November 11, 2026. Report

8. Tenbrief, November 12, 2026. Report

9. Benzinga, November 2026, citing Reuters (May 28). Article (retrieved Nov 13, 2026)

10. DataCenterDynamics, reading of the S-1 update. Article (retrieved Nov 13, 2026)

Disclaimer

This article is for informational purposes only and is not investment advice. investus Research does not recommend buying or selling any security. Figures are from the cited filings and posts; computed values are labeled as our arithmetic.