Nifedipine patent date?

Do you mean the original nifedipine patent (the core compound), or a patent for a specific product/region (e.g., US, EU, salt/formulation/use)? There are multiple patent families dating from the late 1960s onward.

If you want a quick answer: the earliest patentFilings for nifedipine date from the late 1960s, with grant dates around 1969–1970 in major markets. Patents for related salts, formulations, and uses extend into the 1970s–1980s and have since expired in many jurisdictions.

Tell me the jurisdiction and whether you want the filing date, grant date, or a specific patent number, and I can give precise details.