Microsoft Point-to-Point Compression
Microsoft Point-to-Point Compression (MPPC; described in RFC 2118) is a streaming data compression algorithm based on an implementation of Lempel–Ziv using a sliding window buffer. According to Hifn's IP statement, MPPC was patent-encumbered (last US patent granted on 1996-07-02).
Source: Wikipedia — Microsoft Point-to-Point Compression (CC BY-SA 4.0)