In the digital era, the paradigm of commerce has undergone a seismic shift. The internet, a mere tool for communication and information dissemination, has burgeoned into a colossal marketplace, molding various sectors including the auction industry. The United States, being a world leader in software development and digital innovation, has nurtured a lucrative online auction software industry. This piece serves as an exploration of the said industry, delineating key findings and offering insightful analysis for discerning readers.

Online auctions are essentially platforms for buying and selling goods or services by offering them up for bid and subsequently selling them to the highest bidder. Auction software, on the other hand, refers to web or server-based applications that enable the undertaking of online auctions. It offers an array of features including the ability to list products, set minimum bid amounts, monitor bidding, and finalize transactions.

The US online auction software industry is a melting pot of diverse entities, varying in size, business model, and target audience. Giants like eBay with universal offerings contrast sharply with niche players like Bring a Trailer that focus on specialized markets such as vintage cars.

At the temporal intersection of the 21st century, the US online auction software industry is teeming with potential and vibrancy. According to IBIS World, the online auction industry in the US has grown by 4.4% to reach a revenue of $17 billion in 2021, indicating the significant role played by auction software in the US.

In terms of technology, the industry has shown an unprecedented adoption of sophisticated techniques such as artificial intelligence, machine learning, and blockchain technology. AI and machine learning have enhanced the user experience by offering personalized recommendations, accurate price predictions, and advanced fraud detection systems. Blockchain, on the other hand, ensures transparency, security, and trust in transactions, which are integral to auction proceedings.

However, the incorporation of these technologies harbors trade-offs. Advanced technologies necessitate significant investment, a deterrent for smaller players. They also raise privacy and security concerns, requiring stringent measures to ensure user data protection.

It is essential to delve into the economic implications surrounding the industry. Auction platforms alter market dynamics by lowering transaction costs, increasing market efficiency, and creating a global marketplace. Furthermore, they foster competition, which aligns with the principles of consumer sovereignty and market equilibrium posited by microeconomic theory.

The industry's journey has not been devoid of legal implications. Online auctions have been under the scanner for issues like shill bidding, counterfeiting, and breach of contract. Therefore, robust legal frameworks and stringent enforcement become necessary to ensure fair practices.

In the realm of social sciences, the online auction software industry exemplifies the democratization of commerce. It levels the playing field by empowering small businesses and individuals to participate in the global market. However, it also necessitates digital literacy, thereby exacerbating the digital divide.

In conclusion, the US online auction software industry is a dynamic landscape characterized by technological sophistication, economic vibrancy, and social inclusion. However, it also grapples with challenges relating to technology adoption, legal issues, and social inequality. As the curtain of the future unfolds, it remains to be seen how this industry navigates these dichotomies and continues to evolve.