The OBI slim file includes the class BFO_0000003 (without metadata) which is not included in the instructions. The only place that the class is used in the slim file is in the range of the preceded_by and precedes relations. As this class is not included in the instructions I would not expect it to be included in the resulting slim file.
The OBI slim file includes the class BFO_0000003 (without metadata) which is not included in the instructions. The only place that the class is used in the slim file is in the range of the preceded_by and precedes relations. As this class is not included in the instructions I would not expect it to be included in the resulting slim file.