United States v. Edward Soybel, 13 F.4th 584

Grainger experienced unauthorized deletions in its KeepStock system in 2016 and traced intrusions to an IP address assigned to the master router of the Chicago apartment building where Edward Soybel lived.
FBI obtained a 60-day Pen Register Act order to install IP pen registers on the building’s master router and Soybel’s unit; the devices recorded IP routing information and timestamps but not communication content.
Pen-register data showed Soybel’s private IP attempted to access Grainger’s servers hundreds of times and correlated with master-router activity; forensic evidence showed Soybel downloaded the KeepStock client and changed a coworker’s password using remote access.
Soybel was indicted on 12 counts under the Computer Fraud and Abuse Act, including Count 10 for knowingly transmitting a command that caused damage by changing a password.
After the Supreme Court decided Carpenter, Soybel moved to suppress the pen-register evidence; the district court denied suppression based on the good-faith exception, and a jury convicted him on all counts.
On appeal the Seventh Circuit considered whether using an IP pen register to capture IP-address routing data is a Fourth Amendment search requiring a warrant and whether evidence supported Count 10.

Issue	Plaintiff's Argument (Soybel)	Defendant's Argument (Government)	Held
Whether the warrantless use of IP pen registers to collect IP-address routing data is a Fourth Amendment search	Carpenter requires a warrant for digital-location-like data; IP routing data reveals sensitive personal information and thus is protected	IP routing data is like phone numbers in Smith — voluntarily exposed to an ISP (third party) and only routing/timing (no content) was captured, so no warrant required	No Fourth Amendment search; IP pen registers analogous to telephone pen registers in Smith; Carpenter is distinguishable
Sufficiency of evidence that Soybel caused “damage” by changing Hoehne’s password (Count 10)	The reset caused no data loss and KeepStock remained functional; no ‘‘damage’’ as statutorily defined	Reset impaired availability of the system for Hoehne and impeded customer service, satisfying the statutory definition of damage	Evidence sufficient; temporary impairment of availability met §1030(e)(8) definition of damage

Smith v. Maryland, 442 U.S. 735 (pen-register capture of dialed numbers is not a Fourth Amendment search)
Carpenter v. United States, 138 S. Ct. 2206 (warrant required for historical cell-site location information because it reveals a detailed chronicle of movements)
United States v. Ulbricht, 858 F.3d 71 (2d Cir.) (IP-address routing data analogous to telephone numbers for Fourth Amendment purposes)
Katz v. United States, 389 U.S. 347 (subjective expectation of privacy must be one society recognizes as reasonable)
United States v. Miller, 425 U.S. 435 (no expectation of privacy in information voluntarily shared with third parties)
Kyllo v. United States, 533 U.S. 27 (Fourth Amendment protection where technology intrudes into private home details)
Illinois v. Krull, 480 U.S. 340 (good-faith exception allows evidence obtained under a statute later found unconstitutional)