Visitor visa for father inlaw and mother inlaw

[vistaonly]

Hi,

My father in law got visa rejected twice 4 years back ( applied by thier son).
Now they got the new passport (old one expired). Do we need to tell in the
visa form that visa is refused in the past or not. New passport dont have the reference number to the old pass port. This time I am
sponsoring them to have better chances.

Please advise weather to specify the denial in the form or not. Thanks in advance.

[kabkaba]

Yes your father-in-law must mention that in his application. If found under misrepresentation he can be banned for life.