It appears the html code that Bing picks up is:
What controls the generation of this code? (I made the html text red)<div id="bb-miinfohalf" itemscope itemtype="http://data-vocabulary.org/Product" class="lmt">
<h1 id="bbnme" itemprop="name" ... {stuff deleted by poster}
<span class="bb-saleprice">$<span itemprop="price">113.17</span></span>
<span class="hidden" itemprop="availability" content="in stock">in stock</span><meta itemprop="priceCurrency" content="USD">
</div>
There are some items we sell that are drop shipped, and this saying it is in stock is misleading. This is why we do not have stock tracking disabled.