No. 7
Copyright and Neighbouring Rights
199955
as to secure him an equitable share of
the income, corresponding to standards
generally prevailing in similar cases,
may not be waived
such claim
advance,
it
cannot
be
In
enforced,
however, after the lapse of two years
from the time when the owner of'
copyright received knowledge of tile
circurnstances which give rise to the
claim, and the owner of copyright may
not claim to have received such a
knowledge after more than five years.
Non-exercise of'
exclusive rights
20.
Where the user does not
exercise an exclusive right conferred on
him by the owner of copyright, the
latter may revoke the right concerned if
the non-exercise there of was prejudicial
to his legitimate interests. The right of
revocation may be exercised only after
the expiration of the delay stipulated in