This is the 5681st most frequent Polish word.
wspólników
"Partners" or "associates" (in a cooperative or legal context).
the word 'wspólnikom' here is used in the dative case as 'partners' being the indirect object of the verb 'powierzyć' (to entrust).
On postanowił powierzyć tajemnicę swoim wspólnikom.
He decided to entrusted the secret to his partners.
the word 'wspólników' is used in the genitive case indicating possession or association with 'firma' (company).
Firma oraz jej wspólników ponoszą odpowiedzialność za decyzje.
The company and its partners are responsible for the decisions.
the word 'wspólników' is here in the genitive case specifying possession of 'zaniedbania' (negligence).