It appears that BMW has filed three applications filed by BMW for the trademark CSL in the United States. Filed on 19 April 2017, the marks are M2 CSL, M4 CSL, and M8 CSL.

CSL is an acronym for Coupe Sport Leightbau, or Coupe Sport Lightweight, and has not appeared on a BMW vehicle since 2004, when the M3 CSL spent a single year in production, and was limited to 1,400 units.

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