Not necessarily. I3C Controllers manage an active (i.e., dynamic) Pull-Up resistance on SDA, which they can enable and disable as the Bus transitions between Open Drain and Push-Pull mode. This might be a board-level resistor that is switchable (i.e., that can be engaged/disengaged as needed, controlled by an output pin from the Controller), or internal to the Controller, or any combination of the two.

Note: If an I3C Bus has multiple Controller-capable Devices (i.e., one Active Controller and one or more Secondary Controllers), then the Active Controller manages the Pull-Up on SDA.

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