This is the 3785th most frequent Russian word.
экспертами
"Экспертами" means "by experts" or "experts" in the instrumental plural form in English.
In this sentence, 'экспертами' is used as the instrumental plural of 'эксперт', indicating the individuals performing the action as tools or means of problem-solving.
Мы доверили решение проблемы опытным экспертами.
We entrusted the problem-solving to experienced experts.
Here, 'экспертами' serves as the means of the action, representing the authors of the rules.
Эти правила были разработаны экспертами нашего университета.
These rules were developed by the experts of our university.
Here, 'экспертами' shows the origin of the advice, describing those who provided it.