notes that the pack is an optional free download on the Steam game page Square Enix Support Centre Community Archives
However, downloading the .dat files from third-party file hosts is technically copyright infringement. That said, United Abrasives (developer) and Square Enix (publisher) have never pursued users for this pack – they stopped supporting it entirely after the Definitive Edition launched. notes that the pack is an optional free
Kenji loved Sleeping Dogs for its neon-soaked streets and tight combat, but the game's textures felt soft on his 4K monitor. He wanted a high-resolution texture pack that worked whether he bought the game from a DRM-free retailer, GOG, or used his physical disc — something not locked to Steam. He wanted a high-resolution texture pack that worked
While officially listed on Steam, users of non-Steam versions often rely on community-archived versions or standalone installers found on sites like Archive.org Activation: 1. Identify Your Game Version
The official High Resolution Texture Pack for Sleeping Dogs was originally released as a free DLC for the of the game. If you are looking for this for a non-Steam version, the availability depends on which version of the game you own. 1. Identify Your Game Version