The age of majority for signing contracts is 18 in most states, like Texas. There are five or so states that have a higher age than 18. Because your LLC is a legal business form, you must immediately check with a licensed Texas attorney about whether the subject LLC which was set up with a 17-year-old remains a viable entity.
Check with a lawyer in your locale to discuss more of the details.
Good luck to you.
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At first I thought your son could be a passive member if the LLC was manager-managed. It looks like, however, that only persons with "capacity" can be members of a Texas LLC. The exact language of the statute [TX Business Organizations Code 101.102(a)] is as follows:
"A person may be a member of or acquire a membership interest in a limited liability company unless the person lacks capacity apart from this code."
The age of majority in Texas is 18, however, I couldn't find a definition of "capacity" right off the bat. I am fairly certain (but not positive) that the age of capacity is the same as the age of majority.
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