Do/can integration clauses terminate other contracts?

Question

Question 1. Sometimes it's not clear what contracts (especially implied ones) already exist. If parties want to solidify everything in a single written agreement, what's the best way of doing this? It may not be possible/easy to individually expressly terminate each one of the existing contracts. This could be a problem because some contracts contain specific details on how they can be terminated (such as "this contract can be terminated by both parties agreeing to it in writing").

From https://www.lawinsider.com/clause/integration-clause is the following clause enforcable and able to over ride termination conditions set forth in other contracts (emphasis mine)?

Integration Clause. Except for the other Loan Documents, this Agreement constitutes the entire agreement between Bank and Borrower regarding the Loan, and all prior oral or written communications between Borrower and Bank shall be of no further effect or evidentiary value.

OTOH I've seen clauses written like this from a different page on lawinsider.com

Merger Clause. This Agreement..., contains the final, complete and exclusive statement of the agreement between the parties with respect to the transactions contemplated herein, and all prior or contemporaneous written or oral agreements with respect to the subject matter hereof are merged herein.

Technically speaking does this terminate any previous contracts? It seems to say "if we forgot anything from a previous agreement, just include it here".

Question 2. Is there any difference between Merger Clauses, Integration Clauses, Entire Agreement Clauses, or are they all names for the same thing?

Answer 1

Do/can integration clauses terminate other contracts?

If the parties to the other contracts knowingly and willfully accept such clauses, then yes, subject to not affecting other parties' interests in those contracts.

If parties want to solidify everything in a single written agreement, what's the best way of doing this?

It depends on whether the parties opt to "start fresh" in their relation or whether they intend to preserve any pre-existing contract(s). This is accomplished by incorporating one or the other type of clause, accordingly.

Is there any difference between Merger Clauses, Integration Clauses, Entire Agreement Clauses, or are they all names for the same thing?

Clause titles are just for ease of reference. What matters is the language and substance of their contents. For instance, the effect of the language in an improperly titled "Merger" clause could merge nothing and instead literally nullify "all prior or contemporaneous written or oral agreements". That "merger" clause would certainly be enforceable.

A word of caution:

An "Integration Clause" with language (as in the excerpt) that nullifies the evidentiary value of all prior oral or written communications seems suspicious and detrimental to an injured party (that is, in the event of an injury).

Contract law is premised on the covenant of good faith and fair dealing. Since good or bad faith is a subjective state of mind, and malice/bad faith is rarely admitted (see Dalbec v. Gentleman's Companion, Inc., 828 F.2d 921, 927 (2nd Cir. 1987)), prior-act evidence might inferentially prove the absence of a party's good faith. Thus, waiving the evidentiary value of prior communications is detrimental to the injured party.

Although such waiver could and ought to be stricken [in court] under principles of equity, that waiver makes it easier for a corrupt judge to prevent the injured party from obtaining/using crucial evidence that proves the tortfeasor's liability. The corrupt judge can (and does!) force an improper ruling anyway, but that does not mean that a party should act naively by waiving evidentiary value as the sample "Integration Clause" establishes.