ものとする

ものとする is a formal, often bureaucratic or policy-oriented expression that marks a determination, assumption, or decision about how things will be treated or regarded. It frames a future, hypothetical, or agreed-upon condition as if it were true or as a prescribed rule. It is common in legal texts, regulations, meeting resolutions, and formal plans. It can also convey “let us assume” for the sake of discussion, or “we shall assume/consider that…” in planning contexts. It sounds more stiff and distant than everyday spoken Japanese.