The spirit of this market is to see, if all Formula 1 contenders will have removed Internal Combustion Engines (ICE) from their cars. 

It would not require a rule, but it would require that all contenders are free from ICE.

Hydrogen engine -> Does not resolve positive 

Biofuel/Efuel into an engine -> Does not resolve positive 

Creating this market as a response to the president of Formula 1 (motor sports group) stating Formula 1 will "never go electric": 

https://www.businesstimes.com.sg/lifestyle/formula-1-will-never-go-electric-ecclestones-successor