17:43 Jan 7 

… for a company in which a direct *equity* investment is made. That may incidentally be the case here (it doesn't say) but not by virtue of the loan at issue.

08:22 Jan 7 

Yes Sylvie, I use société bénéficiaire= investee

12:04 Jan 6 

It looks like there are 3 parties involved:
Lender - who lends the money (to "loan" is bad English) = Titulaire

Borrower - who borrows the money (and has to pay it and the interest back to the lender) = Bénéficiaire

A financial institution in between (La société débitrice) through which the money goes back and forth (first from the lender to the borrower, then back from the borrower to the lender).

11:24 Jan 6 

Titulaire : Holder/owner of the count, i.e. the Company which loans money to another one;
"Les soussignés s'engagent par ailleurs à veiller à ce que les conditions de déductibilité des intérêts versés par la société bénéficiaire au titulaire soient respectées" = In this sentence, I understand that "société bénéficiaire" is the company which borrows money, because it must pay the interests to the "holder".
Your comments: "société bénéficiaire" might fit both companies: the company which obtains a loan, and the company which must be reimbursed.