 The paper discusses the pre-launch spectral characterization of the operational land imager, OLI, at various levels and compares it to artifacts observed in on-orbit imagery. It concludes that the types and magnitudes of artifacts are consistent with the pre-launch measurements. The OLI's in-band response was characterized using both integrated instrument level measurements and analytical stackup of component measurements, while out-of-band response was measured using a combination of focal plane module, FPM, and optical component level measurements. Spectral variability can induce striping, banding, and other artifacts in the final data products. Analysis showed that the maximum discontinuity between FPMs due to spectral filter differences is 0.35% for selected targets for all bands except where there is almost no signal. The average discontinuity between FPMs is 0.12%. Pre-launch testing identified low levels of spectral crosstalk amongst the three HGCDT, Cirrus, SWIR1 and SWIR2, bands of the OLI, and on-orbit data confirms this crosstalk in the imagery. The strongest crosstalk effect is from the SWIR1 band to the Cirrus band, accounting for about 0.2% of SWIR1 signal leaking into the Cirrus. Though the total crosstalk signal is only a few counts, it is evident in some scenes when the in-band Cirrus signal is very weak. In moist Cirrus-free atmospheres and over typical land surfaces, at least 30% of the Cirrus signal was due to the SWIR1 band. In the SWIR1 and SWIR2 bands, crosstalk accounts for no more than 0.15% of the total signal. This article was authored by Julia A. Barsi, Kenton Lee, Geer Kvaren, and others. We are article.tv, links in the description below.