The biggest variable in U.S. satellite-broadband policy this year is not a headline rule — it is a set of reference parameters most readers will never see. On May 28, 2026, the FCC's Space Bureau opened a proceeding (SB Docket No. 25-157, DA 26-467) seeking comment on potential revisions to the geostationary (GSO) satellite network reference links it adopted just weeks earlier in the Modernizing Spectrum Sharing for Satellite Broadband Report and Order. These reference links are the assumed, stand-in description of a typical GSO satellite operation. They are also the dial that quietly governs how much real spectrum head-room the new framework hands to non-geostationary (NGSO) operators.

To see why a parameter-setting notice deserves the same scrutiny as the rule it serves, follow the logic of the framework it sits inside. When the FCC retired its decades-old Equivalent Power Flux Density limits, it replaced a fixed numeric ceiling with performance-based protection: NGSO systems may transmit up to the point where they would actually degrade a GSO link. But "actually degrade" requires a definition of the GSO link being protected — its assumed antenna performance, geometry and operating conditions. That definition is the reference link. Set it to describe a fragile, easily-degraded GSO system, and NGSO operators must back off, recreating much of the old over-protection. Set it to reflect robust, realistic GSO operations, and NGSO operators capture meaningful additional throughput.

"Ensuring the GSO reference links appropriately reflect typical and widespread GSO satellite operations in the United States will promote efficient spectrum sharing among today's broadband satellite systems."— Federal Register / FCC Space Bureau, source

The word doing the heavy lifting in that sentence is "typical." The Bureau is asking, in effect, what a representative GSO satellite operation looks like today — and the answer is contested precisely because it allocates spectrum value. GSO incumbents have every incentive to argue that the typical, protectable GSO link is more sensitive than the NGSO challengers claim, because a more sensitive reference link forces NGSO systems to throttle more. NGSO operators have the mirror incentive to argue the reference link should reflect modern, hardened GSO equipment that does not need coddling. The comment file in this docket is where that fight gets adjudicated, one technical assumption at a time.

The procedural posture is the opportunity

This is the part of the reform where commercial outcomes are still movable. The underlying Report and Order is a final rule — done, dated, mostly effective in July. The reference-link proceeding, by contrast, is a live comment window: the Bureau states comments are due 30 days after publication and reply comments 45 days after. For an operator on either side of the GSO/NGSO divide, that is a narrow but real chance to shape the parameter that determines the cash value of the spectrum reform. A company that lobbied hard for EPFD repeal and then sits out the reference-link docket has won the headline and risks losing the substance.

The discipline here is to treat the reference-link debate as the place where the abstract "performance-based protection" promise becomes a number. The Report and Order can promise NGSO operators relief from over-protection in principle, but the reference links are what cash that promise — or quietly defer it. An analyst reading only the final rule would conclude the NGSO operators won decisively in May. An analyst reading this follow-on notice would conclude the win is provisional until the reference links are set, and that the margin of victory is still being negotiated through June and into the reply-comment window.

Why this matters beyond two camps

The reference links are not merely a GSO-versus-NGSO referendum; they are the calibration point for the entire U.S. divergence from the legacy international EPFD regime. The FCC's bet is that a domestically tuned, realistic reference link lets American-licensed NGSO capacity outperform what a static global formula would allow, in service of rural and remote broadband. If the reference links are calibrated conservatively, that bet shrinks; the U.S. ends up with a procedurally modern framework that delivers EPFD-like outcomes in practice. If they are calibrated to genuinely "typical and widespread" current GSO operations, the framework delivers the throughput gains the Commission advertised. The distance between those two outcomes is large, and it is being decided in a docket that will never make a headline.

For market participants, the read-through is concrete. Constellation operators counting on improved per-satellite U.S. throughput should treat the reference-link parameters as a material assumption in their capacity models, not a settled input — the number can still move. GSO fleet operators should treat the same docket as their primary remaining lever for protecting link quality now that the EPFD shield is gone. And anyone valuing spectrum-dependent space assets should note that the relevant authority is still being defined: efficient sharing, in the Bureau's own words, depends on getting these reference links right, and "right" is exactly what the comment file is now contesting.

What to watch

The signal to track is the close of the comment and reply-comment windows and the identity of the parties filing. A reference-link record dominated by GSO incumbents will pull the calibration one way; a record dominated by NGSO challengers will pull it the other. The eventual Bureau decision on the reference links — when it lands — will be the document that finally tells operators how much the May reform was actually worth. Until then, the spectrum-sharing reform should be read as a final rule with a provisional payout, and this docket is the receipt that has not yet been written.