Запуталась немного.
Нужен ли глагол "is" в этой фразе "контракт не подписан"

Contract not signed or contract IS not signed

standard English = The contract has not been signed.
shorthand English = Contract not signed.

Example -- standard English:
Cheque 123456 has been paid but cheque 567890 has not been paid.

Example -- shorthand English:
Cheque 123456 -- Paid.
Cheque 567890 -- Not paid.