Patches

From the Portal Wiki

Patches are updates to the game that fix known bugs, glitches, or exploits within the game, and often add new features or balance changes to items, levels, or other game elements.

Although each patch is usually paired with notes detailing what has been altered, some alterations are not mentioned. These undocumented changes rely on the community to notice their existance and therefore report them to others. As such, the exact date of undocumented change implementation will be an estimate.

Patches are listed in reverse-chronological order, with newest patches first.

Full list of Portal 2 patches

2011

Full list of Portal patches