@PatriciaV this section does not represent a partner's basis.
Schedule K-1 box L represents a partner's share of the partnership "book equity" determined on a tax basis and this could be negative due to partnership losses and a thinly capitalized structure.
This is even noted in the instructions to the K-1:
For many reasons, your ending capital account as reported to you by the partnership in item L may not equal the adjusted tax basis in your partnership interest.
Having said that, @ChicagoTaxGuy you are asking a question about TT Business software but it appears you are asking the question from TT Home & Business software which is a personal tax software. Some clarification may be helpful to @PatriciaV
*A reminder that posts in a forum such as this do not constitute tax advice.
Also keep in mind the date of replies, as tax law changes.
