One question asks whether you have to file an English translation of a foreign-language reference.
- § 1.98 Content of information disclosure statement.
- [...]
- (3)(i) A concise explanation of the relevance, as it is presently understood by the individual designated in § 1.56(c) most knowledgeable about the content of the information, of each patent, publication, or other information listed that is not in the English language. The concise explanation may be either separate from applicant’s specification or incorporated therein.
- (ii) A copy of the translation if a written English-language translation of a non-English-language document, or portion thereof, is within the possession, custody, or control of, or is readily available to any individual designated in § 1.56(c).

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English translation might not necessary for claiming a foreign priority (different from IDS; 1.98):
37 CFR 1.55(a)(4) (i): An English language translation of a non English language foreign application is not required except:
A) When the application is involved in an interference
B) When necessary to overcome the date of a reference relied upon by the examiner,
or
C) When specifically required by the examiner.
ii) If an English language translation is required, it must be filed together with a statement that the translation of the certified copy is accurate.