50/50条款属于责任分摊条款，就是在无法确定货物何时发生损坏的情况下，损失由相关方平均分摊。下文列举了保险公司有关该条款的规定：

太平保险有限公司的货物运输保险中附加险条款有如下约定：

“It is agreed and understood that in respect of items insured hereunder:

The Assured hereby undertakes to inspect each item of the interest Insured upon arrival at the contract site for possible damage sustained during transit.

In the case of packed items which are to be left in their packaging until a later date the packaging is to be visually inspected for signs of possible damage and where any such damage is visible the items are to be unpacked and inspected and any damage discovered reported to the Company.

Where the packaging of an item shows no visible signs of damage to such items having been sustained during transit any subsequent damage discovered upon unpacking will be dealt with by the Company and CAR/EAR Insurer according to whether it can clearly be established that such damage was caused before or after arrival at the contract site.

Where it is not possible to clearly establish whether the damage to an item was caused before or after arrival at the contract site it is hereby agreed that the cost of such damage shall be shared equally between the Company and the CAR/EAR insurer.

In the event of a loss being paid under the 50/50 provisions herein whereby 50% of the loss is to be paid by the Company hereunder and 50% of the CAR Insurers. The Company agrees that 50% of the applicable marine policy deductible shall apply to the proportion payable by Company under this Policy.”

中国人寿财产保险股份有限公司的工程保险中运输险、工程险责任分摊条款有如下约定：

“兹经双方同意，本公司要求：

（一）一旦原材料及设备运抵工地，被保险人应立即检验其运输途中可能发生的损失，若裸装货物损失明显，被保险人应在运输险保险单下提出索赔。

（二）若包装的货物未立即开箱，需放置一段时间，则被保险人应观察检验外包装是否有货损迹象。若货损迹象明显，被保险人应在运输险保险单下提出索赔。

（三）若货物外包装无货损迹象，并且货物仍处于包装状态，直至货物开箱时才发现损失，该损失将视作发生在运输期间，除非从损失的性质上有明显的证据表明损失确系发生在运输保险终止后。

（四）若无明显证据确定损失的发生时间，则该损失将由运输保险及本保险各分摊50％。”

来源：

中国保险行业协会官网