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tokens: described in Section 3.2 , 417 out of 47,125 galaxies have AGN-like variability, for an overall variable AGN fraction of 0.9%. In Figure 3 , we show the light-curve standard deviation versus the PTF R -band magnitude for the full sample. In general, the scatter about the median magnitude for a given light curve increases as the magnitude increases, i.e., there is increased scatter in light curves of fainter objects. The sample of low-mass galaxies from the NSAv0 with AGN-like variability is presented in Table 3 . Three examples of low-mass galaxies with AGN-like variability are shown in Figure 4 . Figure 3. Light-curve standard deviation vs. PTF R -band nuclear magnitude. The shaded gray contours show the full population of galaxies from the NSAv0. The blue circles show galaxies we identify as having AGN-like variability. The orange points show the variable AGN from our ancillary samples (described in Section 2.2 ). The typical scatter in a light curve increases toward fainter galaxy nuclei. Figure 4. Three low-mass galaxies with star formation-dominated narrow emission lines and AGN-like variability. These galaxies span from 5 × 10 7 to 2 × 10 9 M ⊙ in stellar mass. The images cutouts (left) are from the DECaLS Legacy Survey browser and are 30′′ on each side. The black circles are the measured PTF R -band magnitude values measured within a 3′′ nuclear aperture. The light curves (right) give the PTF R -band nucleus magnitudes over 5.5 yr. In the light curves, the gray circles are data, the blue line represents the best-fit damped random walk model, and the shaded blue region shows the range of model uncertainties. Table 3 237 Low-mass Galaxies with AGN-like Variability Note. Variability-selected AGNs with M * 10 10 M ⊙ , in order of R.A. NSA ID refers to the ID given in the NSAv0. σ var , σ QSO , and σ notQSO refer to the significance that the given light curve is variable, an AGN, or a false alarm, respectively. Details on these parameters can be found in Section 3.2 . A full version of this table is available in the online version. (This table is available in its entirety in machine-readable form.) Only a portion of this table is shown here to demonstrate its form and content. A machine-readable version of the full table is available. We explore the fraction of variable AGNs as a function of galaxy and light-curve properties. Uncertainties are binomial limits computed following Gehrels ( 1986 ). In Figure 5 , we show the fraction of variability-selected AGNs as a function of host galaxy stellar mass; we find that the AGN fraction increases toward higher stellar masses. In Figure 6 , we show histograms of stellar mass for the full sample and for variable AGNs. The sample of variable AGNs skews toward higher stellar masses; the median stellar mass of the overall sample is , while the median stellar mass of the variability-selected AGN is 8.3 × 10 9 M ⊙ . The pink shaded region in Figures 5 and 6 denote the region , where our sample is