103 engines have an "upside down" spin on filter, so loosening it will cause all the oil to drain out and run down the side of the engine.

For this type of filter installation punching a hole in the top of the filter will allow the oil to drain down, so when you remove it, there is little spillage.

You may be talking about the replaceable cartidge type filter like the one on my erstwhile '84 190E 2.3 with the 102 engine.

Duke