  We present recent X-ray observations of intermediate BL Lac objects (IBLs),
i.e. BL Lacs which are located between high-energy and low-energy peaked BL Lac
objects with respect to alpha_rx. We briefly discuss the statistical properties
of IBLs from the RGB sample and then focus on a detailed broad band spectral
analysis of two objects, namely 1424+2401 and 1055+5644, which were observed
with ASCA and SAX, respectively. In both cases the spectra are steep and we
find significant curvature in 1424+2401 in the sense that the spectrum gets
flatter at both low (< 1 keV) and high energies (> 5 keV). Our results are in
line with the hypothesis of a continuous distribution of synchrotron peak
frequencies among BL Lac objects.
