Currently, GMMR is following the HEC (Pakistan) policies regarding Turnitin Originality Report and Plagiarism.
Zero tolerance Policy on Plagiarism issue. GMMR aims for original script having 10 or below than 10 % Turnitin Originality Report.
However, the Turnitin Originality Report's percentage above 10% (matching/showing the author(s) original/published thesis, article, case project etc.) are acceptable, condition to the submission of the affidavit by the author(s).

HEC relevant Web links:

http://hec.gov.pk/english/services/faculty/Plagiarism/Pages/default.aspx

How to Interpret Originality Report (Guidelines)

Guidelines on 'Ethics of Using Turnitin' for Administrators

Guidelines on 'Ethics of Using Turnitin' for Instructors 

HEC Plagiarism Policy 

Plagiarism Little Book