The iOS 26.3 release candidate contains references to two unreleased M5 family chips, identified as T6051 and T6052. These findings were shared by Nicolás Alvarez with MacRumors.
Chip Identifiers Uncovered
The iOS 26.3 RC mentions distinct identifiers, aligning with Apple's established naming conventions for its powerful silicon:
- T6051 (Platform H17C): This identifier is consistent with an M5 Max chip. Apple has historically used 'C' for its Max series chips.
- T6052 (Platform H17D): This identifier suggests an M5 Ultra chip. The 'D' suffix traditionally denotes Ultra chips within Apple's lineup.
The Missing M5 Pro
Notably absent from the iOS 26.3 code is T6050 H17S, which would be the expected identifier for an M5 Pro chip.
Context and Speculation
Existing rumors indicate new MacBook Pro models, featuring M5 Pro and M5 Max chips, are expected to launch in the coming weeks. The presence of M5 Max and M5 Ultra references, but a complete omission of the M5 Pro, leads to several possibilities.
An M5 Pro chip may exist but has not yet been added to the iOS 26.3 code. Alternatively, Apple could be altering its chip numbering and platform naming strategy. A third scenario suggests Apple might be planning MacBook Pro models that will feature the more powerful M5 Max and even M5 Ultra chips.
Past Apple Max chips have consistently used 'C' lettering (e.g., M1 Max H13C, M4 Max H16C), and Ultra chips have used 'D' lettering (e.g., M1 Ultra H13D, M3 Ultra H15D). While there was no M4 Ultra, an M5 Ultra chip is anticipated for a rumored Mac Studio model in the M5 family. The current absence of M5 Pro indicators alongside the M5 Max and M5 Ultra references remains unclear.