Chessnut chess pieces — Copyright 2015 Alexis Luengas. Apache License 2.0.
Source: https://github.com/LexLuengas/chessnut-pieces/tree/2b8eaf14a31edad7e9deb53b1473e1d4857868a9
SVG files copied unchanged from Lichess lila commit 021039e8ea9e7861a26cc00e06ed5570396d608a.
Lichess supplies optimized SVG versions of the original artwork.
Game2PGN rasterizes these pieces for previews and video exports.
The upstream repository has COPYRIGHT.txt and LICENSE.txt, no NOTICE file.