ものとする・ ものとしてshall; taking it that
Two jobs. In a contract or a set of rules, after what a party is to do, ものとする is "shall". As ものとして, or ending a line in a calculation, it is "take it that": an assumption to work from.
in rules: shall
The applicant shall submit the required documents within ten days of receiving notice.
mid-sentence: take it that
If we don't hear from you, we will take it that you are not coming.
in a calculation: assume
To keep the explanation simple, assume there is no friction.
Shall
Verb (dictionary or ない-form) + ものとする
It comes at the very end. Terms of use are polite: ものとします.
Take it that
Plain form + ものとして/ものとする
Any tense. A noun takes である: 同じ重さであるものとして, taking them to be the same weight.
In contracts and rules: shall
This is how contracts, regulations and terms of use lay down a duty. しないものとする is "shall not", and できるものとする is "may". It is written, not said: being able to read it is enough.
Party B shall report to Party A every month on the progress of the work.
甲 and 乙 are the two sides of a contract: Party A and Party B.
Users shall not take materials off the premises without the administrator's permission.
We may change the content of this service without prior notice.
ものとして: take it that
You fix on one answer and act as if it were so, often because you can't be sure. This one people say: at work, in notices, in careful everyday speech.
Let's take it that he isn't coming and get on with the preparations.
Items with nothing declared are processed as if nothing had changed.
Please carry on as if I weren't here.
Ending a sentence in a problem, an estimate or a model, ものとする states the assumption: "assume that…".
For this estimate, the exchange rate is assumed not to move for a year.
In terms of use, a た-form + ものとします writes that assumption into a rule: "you are taken to have".
If you use this service, you are taken to have agreed to these terms.
Also 同意したものとみなします, which says the same.
Close neighbours
What people say. ことにする is your own decision; ことになっている tells someone a rule that exists. ものとする is the rule itself, on paper.
You're not supposed to use cell phones during exams.
を~とするN2
After a noun, a rule ends in plain とする: A is to be B.
At this museum, admission is free for children of junior high school age and under.
A belief, not a working assumption: "I trust that", "I had assumed"; in the news, ものと思われる, "it is believed that".
The chair had assumed the ceremony would begin on schedule, but a power outage delayed the start.
を前提にN1
You take something as given, an assumption or an agreed condition, and build on it.
Next year's budget was drawn up on the assumption that user numbers would rise every month.
Check yourself
1A club's rules say this. What does it mean?
会員は、
Choose an answer to see why.
2What do they know about the rain?
雨は
Choose an answer to see why.
More detail
Straight after a noun there is no もの: 欠席として扱う, to treat it as an absence. もの is what lets として follow a whole clause.
More sentences
Any change to the terms of the contract shall be agreed by both parties in writing.
Staff shall not disclose to third parties information learned in the course of their work.
The administration department shall keep the facility's usage records for five years.
Answers that arrived after the deadline were treated as not part of this survey.
In this model, the calculation takes all the parts to be the same weight.
In what follows, the user is assumed to have already completed the required authentication.