Compound preposition
A compound preposition does the same job as a plain old preposition, only more tediously. Therefore it is beloved of our old friend the mediocre attorney.
We know that our legal brethren delight in perverting the ordinary use of words - nominalising verbs into nouns, and so on, and the compound preposition is a neat way of co-opting nouns, conjunctions — all kinds — into the servile business of putting one noun in relation to another.
Why, for example, would rights be exercised “under” a contract “by” a party when they could be “subject to execution”<re>Strictly speaking, this is a nominalisation, not a compound preposition, of course.</ref> “on the part of” that party “in accordance with” the contract?
See also
Plain English Anatomy™ Noun | Verb | Adjective | Adverb | Preposition | Conjunction | Latin | Germany | Flannel | Legal triplicate | Nominalisation | Murder your darlings