Recently received a DMCA notice from CEG TEK through my ISP, what should I do?

If, as you claim, you did not do this you could start by ignoring the notice. If you are then sued by Geg Tek you can hire a lawyer to defend you. That will cost you some big bucks. You could try contacting Geg Tek directly and seeing why they think you did this. You can perhaps convince them of the error of their ways. It is always risky entering the legal arena without a lawyer, but in this case I doubt you will step on your foot, but it is always possible.

Do you have any idea who did do the downloading? Was it someone within your household. Possibly they will step up to the plate. Working with an attorney allows you to maintain anonymity to a certain degree. Once you contact them directly, they will know who you are. But working with an attorney will cost you money.

This is a complex and fact specific legal issue. I recommend you seek an attorney familiar with Internet law and cybersecurity to discuss all your legal options. In general, CEG-TEK provides copyright protection services for owners of copyrighted digital media that is downloaded from peer-to-peer file sharing applications such as Bittorrent. If a client’s content is identified as being downloaded on a file sharing service, CEG-Tek mails out a notice under the Digital Millennium Copyright Act (DMCA) to the Internet Service Provider (ISP) and a settlement demand letter to the address registered to the IP address of the Bittorrent client. CEG-TEK sends out numerous demand letters based only on IP addresses seeking individuals to settle quickly or respond so they can gather more information about the alleged copyright violation and pursue the matter. Contacting CEG-TEK without a lawyer may not be in your best interest, especially considering you said the notice was sent to you in error.