Circumstantial evidence points to Dominik Schiener, co-founder of the IOTA Foundation, being the criminal hacker known as Cystomatic aka. Alhalama.
Several pieces of evidence show the connection between the hacker Cystomatic (aka. Alhalama) and Dominik Schiener:

Cystomatic created a MySpace account with the name "Dominik Schiener".
Cystomatic announced a social media marketing project similar to Fileyy.com, Dominik Schiener's first startup.
Cystomatic announced plans to relocate his Affiliate Marketing business (Fileyy.com?) to Malta. As Dominik Schiener, Cystomatic is Italian, speaks German, is a precocious entrepreneur, is working on an Internet Marketing project and is fond of tax havens.
Cystomatic requests quote to create the logo for Fileyy.com. The winning logo was the same used by Fileyy.com and by Dominik Schiener in his LinkedIn page.

The following evidence shows that Cystomatic changed his name to Alhalama and, therefore, Cystomatic and Alhalama are the same person.

In the Hack Forums, Cystomatic says "Nice, tell me again how much of a marketer you are, and how long your crypter will stay FUD". Cystomatic later changes his username to "Alhalama". However, another user has already quoted Cystomatic's sentence and, as a result, the connection between both usernames is revealed.
Alhalama contact details are the same as Cystomatic's.

Crimes committed by Cystomatic aka. Alhalama include hacking and defacing websites, installing keyloggers, selling administration logins, selling site databases, and buying, using and selling remote access trojans.

Alhalama hacks 11 sites on 6 June 2011.
Alhalama defaces 2 sites on 12 June 2011.
Alhalama hacks 1 site on 13 June 2011.
Alhalama sells site admin logins and databases on 18 June 2011.
Alhalama celebrates his success using the Rapzo Keylogger on 21 June 2011.
Alhalama sells a Blackshades VPN and Blackshades RAT. Blackshades infects the victim's computer when the victim visits a malicious webpage (drive-by download). The FBI run operations in 2012 and 2014 to combat the use of Blackshades, which led to the arrest of near 100 people in 19 countries.

After starting IOTA, Dominik Schiener described his hacking experience:

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"I started hacking computer games when I was 14 and then sold these modifications and earned a fair amount of income for my age and effort. With the money, I then tried to build an advertising platform"

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"And so with that experience I started going on this quest, kind of hustling, like bring out what kind of product I should create to make money because at the time I really wanted to be independent. I wanted to make money so I don't rely on anyone".

The IOTA community and investors have the right to know this information. I have posted it in r/Iota and r/IOTAmarkets but the posts have been removed.

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