When can a joint tender benefit from the Article 101(3) TFEU "efficiency defence"?
The joint tender improves the value proposition to the customer, e.g. in terms of price, or, more likely, in terms of quality;
Achieving those efficiencies would not have been possible through a less restrictive alternative, such as hiring personnel or equipment, or teaming up with another firm which is not a competitor;
The joint tender does not "afford such undertakings the possibility of eliminating competition" with respect to the procurement procedure at issue, i.e. the joint tender is unlikely to be the only tender.
Conclusion
Talking to a competitor about price should raise alarm bells for any businessperson. A joint tender can constitute anti-competitive joint selling in violation of Article 101.
Finally, it is worth keeping in mind that there are other theories of harm than joint selling in this area, such as exclusivity clauses and information exchange.
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