Deed laws from 60s and 70s

In the 60s and 70s, did a buyer need to have all family members’ signatures on a Deed for coal/oil/gas?

As a general rule, only those parties that actually sign a document can convey their interest.

Thank you for your response, Rachel.

Rachel is correct.
In Oklahoma a spouse may have an interest known as a spousal homestead right. While the spouse may not have “legal title” he or she is protected in certain situations from becoming homeless by the owner’s deeding or mortgaging away the property.

If your question is whether all siblings have to join a deed, the answer is no but the non-signing family members are not bound. Again, this is general answer which may vary depending on facts.

Thank you very much, Richard!