## 2 Legal Status of Mega-Constellations under International Space Law
### International Telecommunications Union in Regulating Mega-Constellations
#### 2.2.1 Frequency and Orbital Slot Allocation  
The ITU's role in assigning frequencies and orbital slots is critical to preventing conflicts and ensuring that all countries have fair access to space resources. Previously, there has been an issue related to radio frequency spectrum warehousing, which tended to reflect the inaccurate deployment of non-geostationary satellite systems (NGSO) in the Master International Frequency Register. In response, the ITU adopted a milestone-based regulatory approach, requiring operators to demonstrate progress in deploying their satellites to retain their frequency assignments [5,23]. This deployment has been categorized as 10% deployment within two years from the end of the current period to enter into use, 50% within five years, and complete deployment within seven years. This approach helps to manage the risk of \"paper satellites\" [24], where companies file for more slots than they intend to use, potentially blocking other operators. This has created an issue regarding the warehousing of orbital slots and frequencies, especially if the operator has planned to launch numerous satellites [25]. Secondly, the ITU has also adopted Resolution 219 for the responsible utilization of radio frequency spectra, with international cooperation at its core [26]. Therefore, regarding frequency allocations, the ITU does not license spectra and is rather general in nature. Through the World Radio Communication Conferences (WRC)and Regional Radio Communication Conferences (RRC) texts, it leaves the regulation of specific matters to the discretion of each member state, as long as they adhere to the ITU rules, as well as international law. This can be controversial, especially when deciding how much of the spectrum is allocated to each applicant. An example of a national regulator is the USA FCC, whose responsibilities include assigning spectrum licenses and ensuring competitive innovation and efficient communications services. Significantly, the USA FCC mandates that internet service providers deploy and run at least 50% of their constellation within six years of approval; otherwise, they risk losing their permission and their allotted spectrum. Then, by nine years, the entire constellation must be fully deployed [27]. Against this background, it is clear that radio frequencies and orbital positions are absolutely necessary tools for satellite communications. This is simply because, without them, satellites' functionality would be hindered, triggering the interference of radio frequencies, which in turn reduces the quality of communications, leading to harmful interference. The term \"harmful interference\" refers to the unwanted energy that arises from one or more emissions, radiations, or inductions during reception in a radio communication system. This unwanted energy can cause performance degradation, misinterpretation, or the loss of information that could have been obtained had the unwanted energy not been present [28]. Thus, because the need for telecommunications (for satellites and radio frequencies) is crucial, its expansion is significantly determined by the availability of radio frequencies and orbital positions. In order to carry out the international notification, coordination, and registration of radio frequencies and orbital positions, two methods are normally used. The first is the \"first come, first served\" method, which ensures international protection against harmful interference through the proper coordination of assignments within the ITU and registration with the ITU if international protection against harmful interference is desired, or if the assignment will be used for international services or if it is a precaution against harmful interference from the use of a new assignment [28]. The second method is \"a priori planning\", which is essentially used to ensure equitable access to radio frequencies and orbital positions.