The High Court also upheld the injunction granted by District Court prohibiting VM from reproducing SLA's street directory maps, and distributing or selling reproductions of the maps.

VM was also ordered to compensate SLA and pay its legal costs.

Between 1999 and 2003, VM entered into non-exclusive licence agreements with SLA to use SLA's street directory maps and address point data to produce maps. These were then made available on VM's street directory.

SLA had to terminate the licences granted to VM in July 2004, when the latter asserted that its maps at Street Director were independently created and were not substantially reproduced from SLA's maps and data.

However, VM continued to use SLA's maps and data, thereby infringing SLA's copyright.

SLA took action against VM in October 2005 for copyright infringement.

In August 2007, the District Court decided in SLA's favour and granted an injunction restraining VM from infringing SLA's copyright. VM appealed against the District Court's decision to the High Court.

During the hearing of the appeal, SLA was reported to have planted 'errors' in its maps to detect copyright infringements.

Responding to this in a statement on Tuesday, SLA assured the public that these were not errors.

'Rather, they are 'fingerprints' which have been inserted to detect infringers who blindly copy certain identical features in SLA's maps,' it explained.

'These 'fingerprints' do not mislead users and do not affect the accuracy and reliability of its maps.

'They are subtle and minimal, such as the outline of the Fort Gate in Fort Canning Park which is slightly altered in our map from the actual outline on the ground.'

SLA said it has a duty and responsibility to ensure that the rights in its works are protected.

'As with intellectual property rights owners around the world who use various means to protect works, placing 'fingerprints' is one way to detect infringement,' it added.