On 1 March 2011, TIPO opened online file inspection to the general public via its "TIPONet" portal (Chinese language only). The file can be accessed for published applications from 2003 onwards, under the condition that the patent has not yet been granted and no office action has yet been issued. Correspondence between TIPO and the applicant can be checked by a number search. Official documents (e.g. confirmation letters, corrections/amendments, re-examination, search report, etc.) are available as facsimile. Currently, online file inspection is only possible for patents, not for utility models.
TIPONet can be accessed here.
A step-by-step search guide showing how to access a Taiwanese file wrapper is available on the EPO's "Virtual helpdesk" on Asian patent information.