Укажите "ratingCount" или "reviewCount".
<div class="nav-tabs_rating" itemprop="aggregateRating" itemscope itemtype="http://schema.org/AggregateRating">
<span class="rating">
<span style="width:100%" class="value"></span>
</span>
</div><div class="nav-tabs_rating" itemprop="aggregateRating" itemscope itemtype="http://schema.org/AggregateRating">
<span class="nav-tabs_rating_title">Средняя оценка товара</span>
<span class="nav-tabs_rating_num" itemprop="ratingValue">5</span>
<span class="rating">
<span style="width:100%" class="value"></span>
</span>
</div>Подскажите куда копать?
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