Though the form is perfective (see below), the meaning is non-perfective. An alternate interpretation is that it means "to have obtained something in the past and currently possess it". It's generally equivalent to lexical have.
- Affirmative statement: "I have got a pen."
- Negative statement: "I haven't got a pen."
- Question: "Have you got a pen?"
- Affirmative statement: "She has got a pen."
- Negative statement: "She hasn't got a pen."
- question: "Has she got a pen?"
This is mainly used in informal registers of British English. It isn't used in formal (especially written) British English, where independent have offers an alternative. In American English it's found in AAVE, but generally discouraged from formal registers.