IP Address as Digital Footprint Evidence Questioned in Copyright Cases

As a great percentage of copyright offenses nowadays occur in the cyberspace, digital footprints as evidence play an ever more important role in the prosecution of copyright offenses and bring new issues before the court.  Many issues relate to the question: “how do we link the digital footprints to the defendant?” and this question may become quite onerous in the real world, as shown by a judgment rendered by the IP Court last month on a copyright infringement dispute.  Prosecutors of the New Taipei District Prosecutors Office v. Chen, 108 Xing-Zhi-Shang-Yi 24, IP Court (June 2019). 

The case started with a regular web patrol by a major Taiwanese film production studio, which led to a finding that one of the studio’s film works was unauthorizedly shared by means of the peer-to-peer software “BitTorrent” (or “BT” in short) on a social platform called “” based offshore.  As a usual practice, the film studio reported the crime to the police and requested for an investigation.  While the studio was only able to collect the infringers’ Internet protocol (IP) addresses recorded on BT’s log open to all its users, the police managed to identify the locations and registrants of the IP addresses. Hence, these registrants, mostly individuals, were charged of copyright offenses of infringing the public transmission right as well as the reproduction right in the film, since a digital file downloaded with BT software is automatically offered (as a “seed”) for download by other BT users.


While not a few identified IP address registrants reached settlements with the studio, one registrant chose to act otherwise. He pled not guilty and argued that just because his IP address was used to infringe a copyrighted work, this did not prove he was the infringer.  Someone else must have piggybacked on his IP address to commit the crime, he asserted, adding that “all friends visiting my home have my WiFi password.” 

Despite the prosecutor’s strong contention, both the district court and the IP Court sided with the defendant, holding that the prosecutor did not meet the burden of proving the defendant was guilty beyond reasonable doubt.  Particularly, the IP Court indicated: 

While it is possible that the defendant knows who among his relatives and friends downloaded the film, it is unreasonably harsh to request him to disclose that person’s name.  Even if the defendant is to be held responsible for managing the IP address he rents, this fact alone is insufficient for us to attribute the criminal liability to him. 

Moreover, neither the prosecutor nor the police officer in charge had performed a warranted search to seize the defendant’s computer equipment or mobile devices in order to inspect whether the disputed file was retained or had been once saved therein.

Although the IP Court’s decision implies that a warranted search and seizure of a defendant’s dwelling and computer/cell phone might bring forth useful evidence corroborating a charge based on digital footprints like IP addresses, this should not be interpreted as a signal that a search warrant will be henceforth issued on a lenient standard when it comes to illegal film downloading and transmission, because these offenses are not deemed to be serious crimes.  In fact, under the Copyright Law and Code of Criminal Procedures, there is no more appellate level above the IP Court for such cases. 

It is not legally feasible either for the prosecutors or the police to apply for a warrant to access the communication records or the relevant personal data, because the floor of the punishable sentence terms of such offenses do not reach the threshold set by the Communication Security and Surveillance Act. 

Given the above obstacles, it is possible that the “it-was-someone-else” argument will eventually proliferate to become a “standard” and even effective retort against copyright infringement charges based primarily on results of IP address hunting.  How film studios (and perhaps software companies as well) will cope with this challenge and/or adjust their enforcement tactics calls for the local IP community’s continued attention. 

On a final note, how did the police discover the IP address registrants’ identity, given the barrier posed by the Communication Security and Surveillance Act?  The answer is: instead of applying for an access warrant, the police simply visited the telecom company in possession of the needed data and inquired about its willingness to disclose the same voluntarily, since this approach, according to the still dominant view among IP Court judges, is not unlawful. 

The above contents are intended as general discussion of the subject matter only and shall not be deemed as legal advice to any particular case or issue.