  SDSS J092712.65+294344.0 has been proposed as a candidate for a supermassive
black hole (~10^8.8 solar masses) ejected at high speed from the host galactic
nucleus by gravitational radiation recoil, or alternatively for a supermassive
black hole binary. This is based on a blueshift of 2650 km/s of the broad
emission lines ("b-system") relative to the narrow emission lines ("r-system")
presumed to reflect the galaxy velocity. New observations with the Hobby-Eberly
Telescope (HET) confirm the essential features of the spectrum. We note a third
redshift system, characterized by weak, narrow emission lines of [O III] and [O
II] at an intermediate velocity 900 km/s redward of the broad line velocity
("i-system"). A composite spectrum of SDSS QSOs similar to J0927 illustrates
the feasibility of detecting the calcium K absorption line in spectra of
sufficient quality. The i-system may represent the QSO host galaxy or a
companion. Photoionization requires the black hole to be ~3 kpc from the
r-system emitting gas, implying that we are observing the system only 10^6 yr
after the recoil event and contributing to the low probability of observing
such a system. The HET observations give an upper limit of 10 km/s per year on
the rate of change of the velocity difference between the r- and b-systems,
constraining the orbital phase in the binary model. These considerations and
the presence of a cluster of galaxies apparently containing J0927 favor the
idea that this system represents a superposition of two AGN.
