SYSSUBSCRIPTION system table

CREATE TABLE SYS.SYSSUBSCRIPTION (
	publication_id	 UNSIGNED INT NOT NULL,
	user_id	 UNSIGNED INT NOT NULL,
	subscribe_by	 CHAR(128) NOT NULL,
	created	 NUMERIC(20,0) NOT NULL,
	started	 NUMERIC(20,0),
	PRIMARY KEY (publication_id, user_id, subscribe_by),
	FOREIGN KEY REFERENCES SYS.SYSPUBLICATION,
	FOREIGN KEY REFERENCES SYS.SYSREMOTEUSER
);

Each row describes a subscription from one user ID (which must have REMOTE permissions) to one publication.