Agree is Transitive? Please: no, it's not.

On the BBC this morning they spoke of companies disregarding the "agreed protocols" on overtime.

"Agreed protocols"? I don't think so.

This agreed is a participle, a passive participle used attributively. It could be paraphrased as the protocols which were agreed, which is the passive of [The companies] agreed the protocols.

Except, at least in any form of English I was ever exposed to (until very recently) agree is not a transitive verb. You don't "agree something"; you "agree to something" or "on something" - there's a nuance of difference in that the former is something presented to you while the latter you most likely had a hand in crafting. You can "agree with something", which is, again, different: this something is a thought or belief or principle. Things can "agree with" facts or other things - your story doesn't agree with his, for instance.

But in all cases, agree is used with a preposition (or particle, as you like); it's not directly transitive.

My Longman's* agrees with me (hee hee):

If you have the same opinion as someone else, you agree with them. You can also agree with (=approve of) their attitude, ideas, plans, rules etc., or an activity or principle that you approve of: Do you agree with gun control? You agree with people about or on other matters: I agree (with you) about Tom/on politics/about this issue (NOT I agree this issue). If you and others decide on something or arrange to do something after discussing it, you agree on it: We finally agreed on a plan/a date/a solution/a deal. If you accept something, especially something that was not your idea and that you may not like, you agree to it: She agreed to the plan/the date/the solution/the deal (NOT She agreed the plan etc.). You can also agree to do something: They agreed to pay (NOT They accepted to pay.).

Note that (NOT I agree this issue) and that (NOT She agreed the plan etc.)

And yet, in recent years I've heard (primarily if not exclusively) British journalists using in just the transitive, preposition-less way. They agreed a ceasefire, for instance.

And that means they're free to make both passives (the ceasefire was agreed) and attributive participles (the agreed protocols). While the rest of use have to stick with our relative phrases - even with the relativizer left out, as English permits, these are wordier or even awkward: the ceasefire agreed to, the protocols agreed on: Many companies are disregarding the protocols on overtime pay agreed to, or, better, Many companies are disregarding the protocols on overtime pay they agreed to, and even better, Many companies are disregarding the protocols on overtime pay which they had agreed to.

But even though their Many companies are disregarding the agreed protocols on overtime pay is shorter and snappier, it comes at the loss of meaning: are those "agreed on" protocols, or "agreed to"? If the companies are disregarding protocols forced on them, it's a different story than if they are disregarding protocols whose creation they were partners in.

So, can we then say Many companies are disregarding the agreed-upon protocols on overtime? (the agreed-to protocols?) Well, why not? I'm sure you've heard that usage, along with things like the stored-away records, the locked-up shareholders, the put-away books... In fact, there are over a million hits on Google for just "the agreed-upon X" alone.

Don't turn agree into a transitive verb and lose the various meanings that it has - at least, not by dropping the preposition (or particle). Just consider a two-word verb - and make it passive all you like. Can this be agreed on? Sure it can...

* Longman's Advanced American Dictionary, 2005