The word subscription has been traditionally used to refer to magazine and newspaper subscriptions. In English, the meaning has evolved to use a continuous service, whether paid or free (mainly by applying). This service has even extended beyond information delivery to the use of goods, such as regular delivery of consumables.
The translation of "known", which seems to be a very basic word, is not so simple. Although the mathematical term 既知 (kichi; already-know) is sometimes used, this is not a word that business people use every day and not appropriate even for a literal translation. If you have to explain that the word kichi is used because it is a composite of 既に (already) and 知っている (known), this translation is not working. Know's basic meaning of 知る (shiru; know) is the acquisition of knowledge and information by a subject, such as a person or animal. However, "known" is a past participle and refers to a state that the information is widely recognised. The reason why "known" is difficult to understand may be that the kanji character 知 for "knowledge" does not fit the context of the English "known".
The English noun リスト (list) in katakana is well-established, as in the shopping "list". However, many people find the verb リストする (list-suru / do list) unnatural.
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